health science literature review

Health (Nursing, Medicine, Allied Health)

• Find Articles/Databases
• Reference Resources
• Evidence Summaries & Clinical Guidelines
• Drug Information
• Health Data & Statistics
• Patient/Consumer Facing Materials
• Images and Streaming Video
• Grey Literature
• Mobile Apps & "Point of Care" Tools
• Tests & Measures This link opens in a new window
• Citing Sources
• Selecting Databases
• Framing Research Questions
• Crafting a Search
• Narrowing / Filtering a Search
• Expanding a Search
• Cited Reference Searching
• Saving Searches
• Term Glossary
• Critical Appraisal Resources
• What are Literature Reviews?
• Conducting & Reporting Systematic Reviews
• Finding Systematic Reviews
• Tutorials & Tools for Literature Reviews
• Finding Full Text

What are Systematic Reviews? (3 minutes, 24 second YouTube Video)

Systematic Literature Reviews: Steps & Resources

These steps for conducting a systematic literature review are listed below . 

Also see subpages for more information about:

• The different types of literature reviews, including systematic reviews and other evidence synthesis methods
• Tools & Tutorials

Literature Review & Systematic Review Steps

• Develop a Focused Question
• Scope the Literature  (Initial Search)
• Refine & Expand the Search
• Limit the Results
• Download Citations
• Abstract & Analyze
• Create Flow Diagram
• Synthesize & Report Results

1. Develop a Focused   Question 

Consider the PICO Format: Population/Problem, Intervention, Comparison, Outcome

Focus on defining the Population or Problem and Intervention (don't narrow by Comparison or Outcome just yet!)

"What are the effects of the Pilates method for patients with low back pain?"

Tools & Additional Resources:

• PICO Question Help
• Stillwell, Susan B., DNP, RN, CNE; Fineout-Overholt, Ellen, PhD, RN, FNAP, FAAN; Melnyk, Bernadette Mazurek, PhD, RN, CPNP/PMHNP, FNAP, FAAN; Williamson, Kathleen M., PhD, RN Evidence-Based Practice, Step by Step: Asking the Clinical Question, AJN The American Journal of Nursing : March 2010 - Volume 110 - Issue 3 - p 58-61 doi: 10.1097/01.NAJ.0000368959.11129.79

2. Scope the Literature

A "scoping search" investigates the breadth and/or depth of the initial question or may identify a gap in the literature. 

Eligible studies may be located by searching in:

• Background sources (books, point-of-care tools)
• Article databases
• Trial registries
• Grey literature
• Cited references
• Reference lists

When searching, if possible, translate terms to controlled vocabulary of the database. Use text word searching when necessary.

Use Boolean operators to connect search terms:

• Combine separate concepts with AND  (resulting in a narrower search)
• Connecting synonyms with OR  (resulting in an expanded search)

Search:  pilates AND ("low back pain"  OR  backache )

Video Tutorials - Translating PICO Questions into Search Queries

• Translate Your PICO Into a Search in PubMed (YouTube, Carrie Price, 5:11) 
• Translate Your PICO Into a Search in CINAHL (YouTube, Carrie Price, 4:56)

3. Refine & Expand Your Search

Expand your search strategy with synonymous search terms harvested from:

• database thesauri
• reference lists
• relevant studies

Example: 

(pilates OR exercise movement techniques) AND ("low back pain" OR backache* OR sciatica OR lumbago OR spondylosis)

As you develop a final, reproducible strategy for each database, save your strategies in a:

• a personal database account (e.g., MyNCBI for PubMed)
• Log in with your NYU credentials
• Open and "Make a Copy" to create your own tracker for your literature search strategies

4. Limit Your Results

Use database filters to limit your results based on your defined inclusion/exclusion criteria.  In addition to relying on the databases' categorical filters, you may also need to manually screen results.  

• Limit to Article type, e.g.,:  "randomized controlled trial" OR multicenter study
• Limit by publication years, age groups, language, etc.

NOTE: Many databases allow you to filter to "Full Text Only".  This filter is  not recommended . It excludes articles if their full text is not available in that particular database (CINAHL, PubMed, etc), but if the article is relevant, it is important that you are able to read its title and abstract, regardless of 'full text' status. The full text is likely to be accessible through another source (a different database, or Interlibrary Loan).  

• Filters in PubMed
• CINAHL Advanced Searching Tutorial

5. Download Citations

Selected citations and/or entire sets of search results can be downloaded from the database into a citation management tool. If you are conducting a systematic review that will require reporting according to PRISMA standards, a citation manager can help you keep track of the number of articles that came from each database, as well as the number of duplicate records.

In Zotero, you can create a Collection for the combined results set, and sub-collections for the results from each database you search.  You can then use Zotero's 'Duplicate Items" function to find and merge duplicate records.

• Citation Managers - General Guide

6. Abstract and Analyze

• Migrate citations to data collection/extraction tool
• Screen Title/Abstracts for inclusion/exclusion
• Screen and appraise full text for relevance, methods, 
• Resolve disagreements by consensus

Covidence is a web-based tool that enables you to work with a team to screen titles/abstracts and full text for inclusion in your review, as well as extract data from the included studies.

• Covidence Support
• Critical Appraisal Tools
• Data Extraction Tools

7. Create Flow Diagram

The PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) flow diagram is a visual representation of the flow of records through different phases of a systematic review.  It depicts the number of records identified, included and excluded.  It is best used in conjunction with the PRISMA checklist .

Example from: Stotz, S. A., McNealy, K., Begay, R. L., DeSanto, K., Manson, S. M., & Moore, K. R. (2021). Multi-level diabetes prevention and treatment interventions for Native people in the USA and Canada: A scoping review. Current Diabetes Reports, 2 (11), 46. https://doi.org/10.1007/s11892-021-01414-3

• PRISMA Flow Diagram Generator (ShinyApp.io, Haddaway et al. )
• PRISMA Diagram Templates  (Word and PDF)
• Make a copy of the file to fill out the template
• Image can be downloaded as PDF, PNG, JPG, or SVG
• Covidence generates a PRISMA diagram that is automatically updated as records move through the review phases

8. Synthesize & Report Results

There are a number of reporting guideline available to guide the synthesis and reporting of results in systematic literature reviews.

It is common to organize findings in a matrix, also known as a Table of Evidence (ToE).

• Reporting Guidelines for Systematic Reviews
• Download a sample template of a health sciences review matrix  (GoogleSheets)

Steps modified from: 

Cook, D. A., & West, C. P. (2012). Conducting systematic reviews in medical education: a stepwise approach.   Medical Education , 46 (10), 943–952.

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Health Professions Education for Doctoral Students: Reviewing the Literature

• Articles on Your topic
• Reviewing the Literature
• Writing Your Thesis
• Writing & Citing
• Publishing Your Research

What is a Literature Review?

“A review of the literature consists of reading, analyzing, and writing a synthesis of scholarly materials about a specific topic. When the review is of scientific literature, the focus is on the hypotheses, the scientific methods, the strengths and weaknesses of the study, the results, and the authors’ interpretations and conclusions. A review of the scientific literature is fundamental to understanding the accumulated knowledge about the topic being reviewed."

Garrard, J. (2017). Health sciences literature review made easy: The matrix method . Burlington, MA: Jones and Bartlett Learning. p. 4.

Search Strategies

For a review of the literature, you want to conduct a comprehensive search to identify as many sources as possible on your topic. Be sure to take notes on your search process, otherwise it's easy to lose track of what you've already tried.

Database Searching

Search health sciences and other disciplinary databases (i.e. CINAHL, MEDLINE, ERIC) for keywords related to your topic.  (See the  Articles on Your Topic  page of this guide for tips and resources).

Having trouble?   Make an appointment with a librarian  to discuss databases, keywords, and search strategies.

Citation Searching

When you find a relevant article, use it to identify other potentially relevant articles:

Look at its references to identify other relevant articles that you haven't found.

Use Google Scholar or Scopus to identify more recent articles that have cited that one.

Structure of a Literature Review

When you're writing a literature review, you won't just summarize all of the articles that you've found on your topic. Instead, you'll synthesize the evidence. This means that you'll look at the state of the evidence as a whole, telling your reader what it means when you put it all together. Rather than reviewing your sources one at a time, you'll organize your lit review by concept, chronology, methodology, etc. -- whatever makes the most sense for your topic.

The Matrix Method

What is the Matrix Method?

The Matrix Method is an organizational system that guides you through the literature review process from start to finish, outlined in the book Health Sciences Literature Review Made Easy by Judith Garrard (see citation below). It is “intended to teach you how to read a paper, organize the review using the Matrix Method, analyze it, and create a narrative synthesis” (p. 31).

• Matrix Method Handout This handout provides a general introduction to the Matrix Method. Please refer to Garrard’s book for further instructions on using the Matrix Method.

How can I access Garrard’s book?

Garrard, J. (2017).  Health sciences literature review made easy: The matrix method . Burlington, MA: Jones and Bartlett Learning.

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Searching the public health & medical literature more effectively: literature review help.

• Getting Started
• Articles: Searching PubMed This link opens in a new window
• More Sources: Databases, Systematic Reviews, Grey Literature
• Organize Citations & Search Strategies
• Literature Review Help
• Need More Help?

Writing Guides, Manuals, etc.

Literature Review Tips Handouts

Write about something you are passionate about!

• About Literature Reviews (pdf)
• Literature Review Workflow (pdf)
• Search Tips/Search Operators
• Quick Article Evaluation Worksheet (docx)
• Tips for the Literature Review Workflow
• Sample Outline for a Literature Review (docx)

Ten simple rules for writing a literature review . Pautasso M. PLoS Comput Biol. 2013;9(7):e1003149. doi:10.1371/journal.pcbi.1003149

Conducting the Literature Search . Chapter 4 of Chasan-Taber L. Writing Dissertation and Grant Proposals: Epidemiology, Preventive Medicine and Biostatistics. New York: Chapman and Hall/CRC, 2014.

A step-by-step guide to writing a research paper, from idea to full manuscript . Excellent and easy to follow blog post by Dr. Raul Pacheco-Vega.

Data Extraction

Data extraction answers the question “what do the studies tell us?”

At a minimum, consider the following when extracting data from the studies you are reviewing ( source ):

• Only use the data elements relevant to your question;
• Use a table, form, or tool (such as Covidence ) for data extraction;
• Test your methods and tool for missing data elements, redundancy, consistency, clarity.

Here is a table of data elements to consider for your data extraction. (From University of York, Centre for Reviews and Dissemination).

Critical Reading

As you read articles, write notes. You may wish to create a table, answering these questions:

• What is the hypothesis?
• What is the method? Rigorous? Appropriate sample size? Results support conclusions?
• What are the key findings?
• How does this paper support/contradict other work?
• How does it support/contradict your own approach?
• How significant is this research? What is its special contribution?
• Is this research repeating existing approaches or making a new contribution?
• What are its strengths?
• What are its weaknesses/limitations?

From: Kearns, H. & Finn, J. (2017) Supervising PhD Students: A Practical Guide and Toolkit . AU: Thinkwell, p. 103.

Submitting to a Journal? First Identify Journals That Publish on Your Topic

Through Scopus

• Visit the  Scopus database.
• Search for recent articles on your research topic.
• Above the results, click “Analyze search results."
• Click in the "Documents per year by source" box.
• On the left you will see the results listed by the number of articles published on your research topic per journal.

Through Web of Science

• Visit the Web of Science database.
• In the results, click "Analyze Results" on the right hand side.
• From the drop-down menu near the top left, choose "Publication Titles."
• Change the "Minimum record count (threshold)," if desired.
• Scroll down for a table of results by journal title.
• JANE (Journal/Author Name Estimator) Use JANE to help you discover and decide where to publish an article you have authored. Jane matches the abstract of your article to the articles in Medline to find the best matching journals (or authors, or articles).
• Jot (Journal Targeter) Jot uses Jane and other data to determine journals likely to publish your article (based on title, abstract, references) against the impact metric of those journals. From Yale University.
• EndNote Manuscript Matcher Using algorithms and data from the Web of Science and Journal Citation Reports, Manuscript Matcher identifies the most relevant and impactful journals to which one may wish to submit a manuscript. Access Manuscript Matcher via EndNote X9 or EndNote 20.
• DOAJ (Directory of Open Access Journals) Journal Lookup Look up a journal title on DOAJ and find information on publication fees, aims and scope, instructions for authors, submission to publication time, copyright, and more.

Writing Help @UCB

Here is a short list of sources of writing help available to UC Berkeley students, staff, and faculty:

• Purdue OWL Excellent collection of guides on writing, including citing/attribution, citation styles, grammar and punctuation, academic writing, and much more.
• Berkeley Writing: College Writing Programs "Our philosophy includes small class size, careful attention to building your critical reading and thinking skills along with your writing, personalized attention, and a great deal of practice writing and revising." Website has a Writing Resources Database .
• Graduate Writing Center, Berkeley Graduate Division Assists graduate students in the development of academic skills necessary to successfully complete their programs and prepare for future positions. Workshops and online consultations are offered on topics such as academic writing, grant writing, dissertation writing , thesis writing , editing, and preparing articles for publication, in addition to writing groups and individual consultations.
• Nature Masterclass on Scientific Writing and Publishing For Postdocs, Visiting Scholars, and Visiting Student Researchers with active, approved appointments, and current UC Berkeley graduate students who are new to publishing or wish to refresh their skills. Part 1: Writing a Research Paper; Part 2: Publishing a Research Paper; Part 3: Writing and Publishing a Review Paper. Offered by Visiting Researcher Scholar and Postdoc Affairs (VSPA) program; complete this form to gain access.

Alternative Publishing Formats

Here is some information and tips on getting your research to a broader, or to a specialized, audience

• Creating One-Page Reports One-page reports are a great way to provide a snapshot of a project’s activities and impact to stakeholders. Summarizing key facts in a format that is easily and quickly digestible engages the busy reader and can make your project stand out. From EvaluATE .
• How to write an Op-ed (Webinar) Strategies on how to write sharp op-eds for broader consumption, one of the most important ways to ensure your analysis and research is shared in the public sphere. From the Institute for Research on Public Policy .
• 10 tips for commentary writers From UC Berkeley Media Relations’ 2017 Op-Ed writing workshop.
• Journal of Science Policy and Governance JSPG publishes policy memos, op-eds, position papers, and similar items created by students.
• Writing Persuasive Policy Briefs Presentation slides from a UCB Science Policy Group session.
• 3 Essential Steps to Share Research With Popular Audiences (Inside Higher Ed) How to broaden the reach and increase the impact of your academic writing. Popular writing isn’t a distraction from core research!

The Politics of Citation

"One of the feminist practices key to my teaching and research is a feminist practice of citation."

From The Digital Feminist Collective , this blog post emphasizes the power of citing.

"Acknowledging and establishing feminist genealogies is part of the work of producing more just forms of knowledge and intellectual practice."

Here's an exercise (docx) to help you in determining how inclusive you are when citing.

Additional Resources for Inclusive Citation Practices :

• BIPOC Scientists Citation guide (Rockefeller Univ.).
• Conducting Research through an Anti-Racism Lens (Univ. of Minnesota Libraries).
• cleanBib (Code to probabilistically assign gender and race proportions of first/last authors pairs in bibliography entries).
• Balanced Citer (Python script guesses the race and gender of the first and last authors for papers in your citation list and compares your list to expected distributions based on a model that accounts for paper characteristics).
• Read Black women's work;
• Integrate Black women into the CORE of your syllabus (in life & in the classroom);
• Acknowledge Black women's intellectual production;
• Make space for Black women to speak;
• Give Black women the space and time to breathe.
• CiteASista .
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Literature Reviews for the Health Sciences: Introduction

Introduction.

• Research Question
• How to search
• Where to search
• Grey Literature in Health This link opens in a new window
• Reference Management Software
• Resources on Literature Reviews

Literature reviews report the current knowledge on a topic and provide a summary of research from previously published studies. The synthesis of the literature reviewed provides a comprehensive overview of the knowledge available on the topic.

The Literature review also builds a case or identifies a research gap which assists an author in positioning his or her own work in the context of the previous studies (Baker 2016).

A literature review is a search and evaluation of the available literature in your chosen topic area; it documents the state of the art with respect to the topic you are writing about.

The process:

• Surveys the literature in your chosen area of study
• Synthesises the information in that literature into a summary
• Critically analyses the information gathered, identifies gaps in the current knowledge, showing limitations of theories and points of view and formulating areas for further research

Types of Literature Reviews

The Purpose of the Literature Review

Related / useful uc library guides.

Baker, Joy. (2016). The Purpose, Process, and Methods of Writing a Literature Review. AORN journal. 103. 265-269. 10.1016/j.aorn.2016.01.016. 

Frey, B. (2018).  The SAGE encyclopedia of educational research, measurement, and evaluation  (Vols. 1-4). Thousand Oaks,, CA: SAGE Publications, Inc. doi: 10.4135/9781506326139

Grant, M.J. and Booth, A. (2009), A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information & Libraries Journal, 26: 91-108.  https://doi.org/10.1111/j.1471-1842.2009.00848.x

Tricco, AC, Lillie, E, Zarin, W, O'Brien, KK, Colquhoun, H, Levac, D, Moher, D, Peters, MD, Horsley, T, Weeks, L, Hempel, S et al. PRISMA extension for scoping reviews (PRISMA-ScR): checklist and explanation. Ann Intern Med. 2018,169(7):467-473.  doi:10.7326/M18-0850.

Tricco AC, Lillie E, Zarin W, O'Brien KK, Colquhoun H, Levac D, Moher D, Peters MDJ, Horsley T, Weeks L, Hempel S, Akl EA, Chang C, McGowan J, Stewart L, Hartling L, Aldcroft A, Wilson MG, Garritty C, Lewin S, Godfrey CM, Macdonald MT, Langlois EV, Soares-Weiser K, Moriarty J, Clifford T, Tunçalp Ö, Straus SE. PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation. Ann Intern Med. 2018 Oct 2;169(7):467-473. doi: 10.7326/M18-0850. Epub 2018 Sep 4. PMID: 30178033.

(1) Griffith University subject guides : https://libraryguides.griffith.edu.au/systematic-literature-reviews-for-education/introduction 

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7 Writing a Literature Review

Hundreds of original investigation research articles on health science topics are published each year. It is becoming harder and harder to keep on top of all new findings in a topic area and – more importantly – to work out how they all fit together to determine our current understanding of a topic. This is where literature reviews come in.

In this chapter, we explain what a literature review is and outline the stages involved in writing one. We also provide practical tips on how to communicate the results of a review of current literature on a topic in the format of a literature review.

7.1 What is a literature review?

Literature reviews provide a synthesis and evaluation  of the existing literature on a particular topic with the aim of gaining a new, deeper understanding of the topic.

Published literature reviews are typically written by scientists who are experts in that particular area of science. Usually, they will be widely published as authors of their own original work, making them highly qualified to author a literature review.

However, literature reviews are still subject to peer review before being published. Literature reviews provide an important bridge between the expert scientific community and many other communities, such as science journalists, teachers, and medical and allied health professionals. When the most up-to-date knowledge reaches such audiences, it is more likely that this information will find its way to the general public. When this happens, – the ultimate good of science can be realised.

A literature review is structured differently from an original research article. It is developed based on themes, rather than stages of the scientific method.

In the article Ten simple rules for writing a literature review , Marco Pautasso explains the importance of literature reviews:

Literature reviews are in great demand in most scientific fields. Their need stems from the ever-increasing output of scientific publications. For example, compared to 1991, in 2008 three, eight, and forty times more papers were indexed in Web of Science on malaria, obesity, and biodiversity, respectively. Given such mountains of papers, scientists cannot be expected to examine in detail every single new paper relevant to their interests. Thus, it is both advantageous and necessary to rely on regular summaries of the recent literature. Although recognition for scientists mainly comes from primary research, timely literature reviews can lead to new synthetic insights and are often widely read. For such summaries to be useful, however, they need to be compiled in a professional way (Pautasso, 2013, para. 1).

An example of a literature review is shown in Figure 7.1.

Video 7.1: What is a literature review? [2 mins, 11 secs]

Watch this video created by Steely Library at Northern Kentucky Library called ‘ What is a literature review? Note: Closed captions are available by clicking on the CC button below.

Examples of published literature reviews

• Strength training alone, exercise therapy alone, and exercise therapy with passive manual mobilisation each reduce pain and disability in people with knee osteoarthritis: a systematic review
• Traveler’s diarrhea: a clinical review
• Cultural concepts of distress and psychiatric disorders: literature review and research recommendations for global mental health epidemiology

7.2 Steps of writing a literature review

Writing a literature review is a very challenging task. Figure 7.2 summarises the steps of writing a literature review. Depending on why you are writing your literature review, you may be given a topic area, or may choose a topic that particularly interests you or is related to a research project that you wish to undertake.

Chapter 6 provides instructions on finding scientific literature that would form the basis for your literature review.

Once you have your topic and have accessed the literature, the next stages (analysis, synthesis and evaluation) are challenging. Next, we look at these important cognitive skills student scientists will need to develop and employ to successfully write a literature review, and provide some guidance for navigating these stages.

Analysis, synthesis and evaluation

Analysis, synthesis and evaluation are three essential skills required by scientists  and you will need to develop these skills if you are to write a good literature review ( Figure 7.3 ). These important cognitive skills are discussed in more detail in Chapter 9.

The first step in writing a literature review is to analyse the original investigation research papers that you have gathered related to your topic.

Analysis requires examining the papers methodically and in detail, so you can understand and interpret aspects of the study described in each research article.

An analysis grid is a simple tool you can use to help with the careful examination and breakdown of each paper. This tool will allow you to create a concise summary of each research paper; see Table 7.1 for an example of  an analysis grid. When filling in the grid, the aim is to draw out key aspects of each research paper. Use a different row for each paper, and a different column for each aspect of the paper ( Tables 7.2 and 7.3 show how completed analysis grid may look).

Before completing your own grid, look at these examples and note the types of information that have been included, as well as the level of detail. Completing an analysis grid with a sufficient level of detail will help you to complete the synthesis and evaluation stages effectively. This grid will allow you to more easily observe similarities and differences across the findings of the research papers and to identify possible explanations (e.g., differences in methodologies employed) for observed differences between the findings of different research papers.

Table 7.1: Example of an analysis grid

Table 7.3: Sample filled-in analysis grid for research article by Ping and colleagues

Source: Ping, WC, Keong, CC & Bandyopadhyay, A 2010, ‘Effects of acute supplementation of caffeine on cardiorespiratory responses during endurance running in a hot and humid climate’, Indian Journal of Medical Research, vol. 132, pp. 36–41. Used under a CC-BY-NC-SA licence.

Step two of writing a literature review is synthesis.

Synthesis describes combining separate components or elements to form a connected whole.

You will use the results of your analysis to find themes to build your literature review around. Each of the themes identified will become a subheading within the body of your literature review.

A good place to start when identifying themes is with the dependent variables (results/findings) that were investigated in the research studies.

Because all of the research articles you are incorporating into your literature review are related to your topic, it is likely that they have similar study designs and have measured similar dependent variables. Review the ‘Results’ column of your analysis grid. You may like to collate the common themes in a synthesis grid (see, for example Table 7.4 ).

Step three of writing a literature review is evaluation, which can only be done after carefully analysing your research papers and synthesising the common themes (findings).

During the evaluation stage, you are making judgements on the themes presented in the research articles that you have read. This includes providing physiological explanations for the findings. It may be useful to refer to the discussion section of published original investigation research papers, or another literature review, where the authors may mention tested or hypothetical physiological mechanisms that may explain their findings.

When the findings of the investigations related to a particular theme are inconsistent (e.g., one study shows that caffeine effects performance and another study shows that caffeine had no effect on performance) you should attempt to provide explanations of why the results differ, including physiological explanations. A good place to start is by comparing the methodologies to determine if there are any differences that may explain the differences in the findings (see the ‘Experimental design’ column of your analysis grid). An example of evaluation is shown in the examples that follow in this section, under ‘Running performance’ and ‘RPE ratings’.

When the findings of the papers related to a particular theme are consistent (e.g., caffeine had no effect on oxygen uptake in both studies) an evaluation should include an explanation of why the results are similar. Once again, include physiological explanations. It is still a good idea to compare methodologies as a background to the evaluation. An example of evaluation is shown in the following under ‘Oxygen consumption’.

7.3 Writing your literature review

Once you have completed the analysis, and synthesis grids and written your evaluation of the research papers , you can combine synthesis and evaluation information to create a paragraph for a literature review ( Figure 7.4 ).

The following paragraphs are an example of combining the outcome of the synthesis and evaluation stages to produce a paragraph for a literature review.

Note that this is an example using only two papers – most literature reviews would be presenting information on many more papers than this ( (e.g., 106 papers in the review article by Bain and colleagues discussed later in this chapter). However, the same principle applies regardless of the number of papers reviewed.

The next part of this chapter looks at the each section of a literature review and explains how to write them by referring to a review article that was published in Frontiers in Physiology and shown in Figure 7.1. Each section from the published article is annotated to highlight important features of the format of the review article, and identifies the synthesis and evaluation information.

In the examination of each review article section we will point out examples of how the authors have presented certain information and where they display application of important cognitive processes; we will use the colour code shown below:

This should be one paragraph that accurately reflects the contents of the review article.

Introduction

The introduction should establish the context and importance of the review

Body of literature review

The reference section provides a list of the references that you cited in the body of your review article. The format will depend on the journal of publication as each journal has their own specific referencing format.

It is important to accurately cite references in research papers to acknowledge your sources and ensure credit is appropriately given to authors of work you have referred to. An accurate and comprehensive reference list also shows your readers that you are well-read in your topic area and are aware of the key papers that provide the context to your research.

It is important to keep track of your resources and to reference them consistently in the format required by the publication in which your work will appear. Most scientists will use reference management software to store details of all of the journal articles (and other sources) they use while writing their review article. This software also automates the process of adding in-text references and creating a reference list. In the review article by Bain et al. (2014) used as an example in this chapter, the reference list contains 106 items, so you can imagine how much help referencing software would be. Chapter 5 shows you how to use EndNote, one example of reference management software.

Click the drop down below to review the terms learned from this chapter.

Copyright note:

• The quotation from Pautasso, M 2013, ‘Ten simple rules for writing a literature review’, PLoS Computational Biology is use under a CC-BY licence. 
• Content from the annotated article and tables are based on Schubert, MM, Astorino, TA & Azevedo, JJL 2013, ‘The effects of caffeinated ‘energy shots’ on time trial performance’, Nutrients, vol. 5, no. 6, pp. 2062–2075 (used under a CC-BY 3.0 licence ) and P ing, WC, Keong , CC & Bandyopadhyay, A 2010, ‘Effects of acute supplementation of caffeine on cardiorespiratory responses during endurance running in a hot and humid climate’, Indian Journal of Medical Research, vol. 132, pp. 36–41 (used under a CC-BY-NC-SA 4.0 licence ). 

Bain, A.R., Morrison, S.A., & Ainslie, P.N. (2014). Cerebral oxygenation and hyperthermia. Frontiers in Physiology, 5 , 92.

Pautasso, M. (2013). Ten simple rules for writing a literature review. PLoS Computational Biology, 9 (7), e1003149.

How To Do Science Copyright © 2022 by University of Southern Queensland is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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Review Articles (Health Sciences)

• Finding Review Articles
• Goals of a Literature Review
• Select Citation Management Software
• Select databases to search
• Track your searches
• Conduct searches
• Select articles to include
• Extract information from articles
• Structure your review
• Find "fill-in" information
• Other sources and help
• Systematic Reviews
• Other types of reviews

This guide provides one possible process for developing and writing a literature review. There is no single process for developing and writing a literature review; this is only one example. If you are writing a literature review for a class, as part of a research project, or for publication, examine the requirements and suggestions from your faculty instructor, research team lead, or the editor, and adapt these steps as needed. You can also find different processes for literature reviews in other handbooks and textbooks.

While this is presented as a single process, you may find yourself conducting the steps in a different order, or repeating some steps multiple times. Every person approaches a literature review differently-- this is expected.

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• Literature Reviews in the Health Sciences
• Review Comparison Chart
• Decision Tools
• Systematic Review
• Meta-Analysis
• Scoping Review
• Mapping Review
• Integrative Review
• Rapid Review
• Realist Review
• Umbrella Review
• Review of Complex Interventions
• Diagnostic Test Accuracy Review
• Narrative Literature Reviews
• Standards and Guidelines

Navigate the links below to jump to a specific section of the page:

When is a Scoping Review methodology appropriate?

Outline of stages, methods and guidance, examples of scoping reviews, supplementary resources.

According to Colquhoun et al. (2014) , a scoping review can be defined as: "a form of knowledge synthesis, which incorporate a range of study designs to comprehensively summarize and synthesize evidence with the aim of informing practice, programs, and policy and providing direction to future research priorities" (p.1291).

Characteristics

• Answers a broad question
• Scoping reviews serve the purpose of identifying the scope and extent of existing research on a topic
• Similar to systematic reviews, scoping reviews follow a step-by-step process and aim to be transparent and replicable in its methods

When to Use It: A scoping review might be right for you if you are interested in:

• Examining the extent, range, and nature of research activity
• Determining the value of undertaking a full systematic review (e.g. Do any studies exist? Have systematic reviews already been conducted?)
• Summarizing the disseminating research findings
• Identifying gaps in an existing body of literature

The following stages of conducting a review of complex interventions are derived from  Peters et al. (2015)  and Levac et al. (2010) .

Timeframe:  12+ months, (same amount of time as a systematic review or longer)

*Varies beyond the type of review. Depends on many factors such as but not limited to: resources available, the quantity and quality of the literature, and the expertise or experience of reviewers" ( Grant & Booth, 2009 ).

Question:  Answers broader and topic focused questions beyond those relating to the effectiveness of treatments or interventions. A priori review protocol is recommended. 

Is your review question a complex intervention? Learn more about  Reviews of Complex Interventions .

Sources and searches:  Comprehensive search-may be limited by time/scope restraints, still aims to be thorough and repeatable of all literature. May involve multiple structured searches rather than a single structured search. This will produce more results than a systematic review. Must include a modified PRISMA flow diagram.

Selection:  Based on inclusion/exclusion criteria, due to the iterative nature of a scoping review some changes may be necessary. May require more time spent screening articles due to the larger volume of results from broader questions.

Appraisal:  Critical appraisal (optional), Risk of Bias assessment (optional) is not applicable for scoping reviews. 

Synthesis:  (Tabular with some narrative) The extraction of data for a scoping review may include a charting table or form but a formal synthesis of findings from individual studies and the generation of a 'summary of findings' (SOF) table is not required. Results may include a logical diagram or table or any descriptive form that aligns with the scope and objectives of the review. May incorporate a numerical summary and qualitative thematic analysis.

Consultation:  (optional) 

The following resources provide methods and guidance in the field of scoping reviews.

Methods & Guidance

• Cochrane Training: Scoping reviews: what they are and how you can do them A series of videos presented by Dr Andrea C. Tricco and Kafayat Oboirien. Learn the about what a scoping review is, see examples, learn the steps involved, and common methods from Dr. Tricco. Oboirien presents her experiences of conducting a scoping review on strengthening clinical governance in low and middle income countries.
• Current Best Practices for the Conduct of Scoping Reviews by Heather Colquhoun An overview on best practices when executing a scoping review.
• Joanna Briggs Institute (JBI) Manual for Evidence Synthesis. Chapter 11: Scoping Reviews An extensive and detailed outline within the JBI Manual for Evidence Synthesis on how to properly conduct a scoping review.

Reporting Guideline

• PRISMA for Scoping Reviews (PRISMA-ScR) Contains a 20-item checklist for proper reporting of a scoping review plus 2 optional items.
• Håkonsen, S. J., Pedersen, P. U., Bjerrum, M., Bygholm, A., & Peters, M. (2018). Nursing minimum data sets for documenting nutritional care for adults in primary healthcare: a scoping review .  JBI database of systematic reviews and implementation reports ,  16 (1), 117–139. doi: 10.11124/JBISRIR-2017-003386
• Kao, S. S., Peters, M., Dharmawardana, N., Stew, B., & Ooi, E. H. (2017). Scoping review of pediatric tonsillectomy quality of life assessment instruments .  The Laryngoscope ,  127 (10), 2399–2406. doi: 10.1002/lary.26522
• Tricco, A. C., Zarin, W., Rios, P., Nincic, V., Khan, P. A., Ghassemi, M., Diaz, S., Pham, B., Straus, S. E., & Langlois, E. V. (2018). Engaging policy-makers, health system managers, and policy analysts in the knowledge synthesis process: a scoping review .  Implementation science: IS ,  13 (1), 31. doi: 10.1186/s13012-018-0717-x

Anderson, S., Allen, P., Peckham, S., & Goodwin, N. (2008). Asking the right questions: scoping studies in the commissioning of research on the organisation and delivery of health services .  Health research policy and systems ,  6 , 7. doi: 10.1186/1478-4505-6-7

Arksey, H., & O'Malley, L. (2005). Scoping studies: towards a methodological framework .  International journal of social research methodology, 8 (1), 19-32. doi: 10.1080/1364557032000119616

Armstrong, R., Hall, B. J., Doyle, J., & Waters, E. (2011). Cochrane Update. 'Scoping the scope' of a cochrane review .  Journal of public health (Oxford, England) ,  33 (1), 147–150. doi: 10.1093/pubmed/fdr015

Colquhoun, H. (2016). Current best practices for the conducting of scoping reviews . Symposium Presentation - Impactful Biomedical Research: Achieving Quality and Transparency . https://www.equator-network.org/wp-content/uploads/2016/06/Gerstein-Library-scoping-reviews_May-12.pdf

Colquhoun, H. L., Levac, D., O'Brien, K. K., Straus, S., Tricco, A. C., Perrier, L., Kastner, M., & Moher, D. (2014). Scoping reviews: time for clarity in definition, methods, and reporting .  Journal of clinical epidemiology ,  67 (12), 1291–1294. doi: 10.1016/j.jclinepi.2014.03.013

Davis, K., Drey, N., & Gould, D. (2009). What are scoping studies? A review of the nursing literature .  International journal of nursing studies ,  46 (10), 1386–1400. doi: 10.1016/j.ijnurstu.2009.02.010

Khalil, H., Peters, M., Godfrey, C. M., McInerney, P., Soares, C. B., & Parker, D. (2016). An evidence-based approach to scoping reviews .  Worldviews on evidence-based nursing ,  13 (2), 118–123. doi: 10.1111/wvn.12144

Levac, D., Colquhoun, H., & O'Brien, K. K. (2010). Scoping studies: advancing the methodology .  Implementation science: IS ,  5 , 69. doi: 10.1186/1748-5908-5-69

Lockwood, C., Dos Santos, K. B., & Pap, R. (2019). Practical guidance for knowledge synthesis: scoping review methods .  Asian nursing research ,  13 (5), 287–294. doi: 10.1016/j.anr.2019.11.002

Morris, M., Boruff, J. T., & Gore, G. C. (2016). Scoping reviews: establishing the role of the librarian .  Journal of the Medical Library Association: JMLA ,  104 (4), 346–354. doi: 10.3163/1536-5050.104.4.020

Munn, Z., Peters, M., Stern, C., Tufanaru, C., McArthur, A., & Aromataris, E. (2018). Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach .  BMC medical research methodology ,  18 (1), 143. doi: 10.1186/s12874-018-0611-x

O'Brien, K. K., Colquhoun, H., Levac, D., Baxter, L., Tricco, A. C., Straus, S., Wickerson, L., Nayar, A., Moher, D., & O'Malley, L. (2016). Advancing scoping study methodology: a web-based survey and consultation of perceptions on terminology, definition and methodological steps .  BMC health services research ,  16 , 305. doi: 10.1186/s12913-016-1579-z

Peters, M. D., Godfrey, C. M., Khalil, H., McInerney, P., Parker, D., & Soares, C. B. (2015). Guidance for conducting systematic scoping reviews .  International journal of evidence-based healthcare ,  13 (3), 141–146. doi: 10.1097/XEB.0000000000000050

Peters, M. D. J., Godfrey, C., McInerney, P., Munn, Z., Tricco, A. C., & Khalil, H. (2020). Chapter 11: Scoping Reviews . In Aromataris, E. & Munn, Z. (Eds.),  JBI Manual for Evidence Synthesis . Joanna Briggs Institute. doi: 10.46658/JBIMES-20-12

Peters, M., Marnie, C., Tricco, A. C., Pollock, D., Munn, Z., Alexander, L., McInerney, P., Godfrey, C. M., & Khalil, H. (2021). Updated methodological guidance for the conduct of scoping reviews .  JBI evidence implementation ,  19 (1), 3–10. doi: 10.1097/XEB.0000000000000277

Pham, M. T., Rajić, A., Greig, J. D., Sargeant, J. M., Papadopoulos, A., & McEwen, S. A. (2014). A scoping review of scoping reviews: advancing the approach and enhancing the consistency .  Research synthesis methods ,  5 (4), 371–385. doi: 10.1002/jrsm.1123

Tricco, A. C., Lillie, E., Zarin, W., O'Brien, K. K., Colquhoun, H., Levac, D., Moher, D., Peters, M., Horsley, T., Weeks, L., Hempel, S., Akl, E. A., Chang, C., McGowan, J., Stewart, L., Hartling, L., Aldcroft, A., Wilson, M. G., Garritty, C., Lewin, S., … Straus, S. E. (2018). PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation .  Annals of internal medicine ,  169 (7), 467–473. doi: 10.7326/M18-0850

Tricco, A., Oboirien, K., Lotfi, T., & Sambunjak, D. (2017, August).  Scoping reviews: what they are and how you can do them . Cochrane Training. https://training.cochrane.org/resource/scoping-reviews-what-they-are-and-how-you-can-do-them

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Other Names for a Scoping Review

• Scoping Study
• Systematic Scoping Review
• Scoping Report
• Scope of the Evidence
• Rapid Scoping Review
• Structured Literature Review
• Scoping Project
• Scoping Meta Review

Limitations of a Scoping Review

The following challenges of conducting a scoping review are derived from Grant & Booth (2009) , Peters et al. (2015) , and O'Brien (2016) .

• Is not easier than a systematic review.
• Is not faster than a systematic review; may take longer .
• More citations to screen.
• Different screening criteria/process than a systematic review.
• Often leads to a broader, less defined search.
• Requires multiple structured searches instead of one.
• Increased emphasis for hand searching the literature.
• May require larger teams because of larger volume of literature.
• Inconsistency in the conduct of scoping reviews.

Medical Librarian

• Last Updated: Sep 5, 2023 11:14 AM
• URL: https://guides.lib.uh.edu/reviews

Writing in the Health Sciences: Research and Lit Reviews

• Research and Lit Reviews
• Tables and Figures
• Citation Management
• Further Reference

What Is a Literature Review?

In simple terms, a literature review investigates the available information on a certain topic. It may be only a knowledge survey with an intentional focus. However, it is often a well-organized examination of the existing research which evaluates each resource in a systematic way. Often a lit review will involve a series of inclusion/exclusion criteria or an assessment rubric which examines the research in-depth. Below are some interesting sources to consider.

The Writing Center's Literature Reviews - UNC-Chapel Hill's writing center explains some of the key criteria involved in doing a literature review.

Literature Review vs. Systematic Review - This recent article details the difference between a literature review and a systematic review. Though the two share similar attributes, key differences are identified here.

Literature Review Steps

1. Identify a research question. For example: "Does the use of warfarin in elderly patients recovering from myocardial infarction help prevent stroke?"

2. Consider which databases might provide information for your topic. Often PubMed or CINAHL will cover a wide spectrum of biomedical issues. However, other databases and grey literature sources may specialize in certain disciplines. Embase is generally comprehensive but also specializes in pharmacological interventions.

3. Select the major subjects or ideas from your question.  Focus in on the particular concepts involved in your research. Then brainstorm synonyms and related terminology for these topics.

4. Look for the  preferred indexing terms for each concept in your question. This is especially important with databases such as PubMed, CINAHL, or Scopus where headings within the MeSH database or under the Emtree umbrella are present.  For example, the above question's keywords such as " warfarin " or "myocardial infarction" can involve related terminology or subject headings such as "anti-coagulants" or "cardiovascular disease."

5. Build your search using boolean operators. Combine the synonyms in your database using boolean operators such as AND or OR. Sometimes it is necessary to research parts of a question rather than the whole. So you might link searches for things like the preventive effects of anti-coagulants with stroke or embolism, then AND these results with the therapy for patients with cardiovascular disease.

6. Filter and save your search results from the first database (do this for all databases). This may be a short list because of your topic's limitations, but it should be no longer than 15 articles for an initial search. Make sure your list is saved or archived and presents you with what's needed to access the full text.

7. Use the same process with the next databases on your list. But pay attention to how certain major headings may alter the terminology. "Stroke" may have a suggested term of "embolism" or even "cerebrovascular incident" depending on the database.

8. Read through the material for inclusion/exclusion . Based on your project's criteria and objective, consider which studies or reviews deserve to be included and which should be discarded. Make sure the information you have permits you to go forward. 

9. Write the literature review. Begin by summarizing why your research is important and explain why your approach will help fill gaps in current knowledge. Then incorporate how the information you've selected will help you to do this. You do not need to write about all of the included research you've chosen, only the most pe rtinent.

10. Select the most relevant literature for inclusion in the body of your report. Choose the articles and data sets that are most particularly relevant to your experimental approach. Consider how you might arrange these sources in the body of your draft. 

Library Books

Call #: WZ 345 G192h 2011

ISBN #: 9780763771867

This book details a practical, step-by-step method for conducting a literature review in the health sciences. Aiming to  synthesize the information while also analyzing it, the Matrix Indexing System enables users to establish a  structured process for tracking, organizing and integrating the knowledge within a collection.

Key Research Databases

PubMed -  The premier medical database for review articles in medicine, nursing, healthcare, other related biomedical disciplines. PubMed contains over 20 million citations and can be navigated through multiple database capabilities and searching strategies.

CINAHL Ultimate - Offers comprehensive coverage of health science literature. CINAHL is particularly useful for those researching the allied disciplines of nursing, medicine, and pharmaceutical sciences.

Scopus - Database with over 12 million abstracts and citations which include peer-reviewed titles from international and Open Access journals. Also includes interactive bibliometrics and researcher profiling.

Embase - Elsevier's fully interoperable database of both Medline and Emtree-indexed articles. Embase also specializes in pharmacologic interventions.

Cochrane - Selected evidence-based medicine resources from the Cochrane Collaboration that includes peer-reviewed systematic reviews and randomized controlled trials. Access this database through OVID with TTUHSC Libraries.

DARE - Literally the Datatase of Abstracts of Reviews of Effectiveness, this collection of systematic reviews and other evidence-based research contains critical assessments from a wide variety of medical journals.

TRIP - This TRIP database is structured according to the level of evidence for its EBM content. It allows users to quickly and easily locate high-quality, accredited medical literature for clinical and research purposes.

Web of Science - Contains bibliographic articles and data from a wide variety of publications in the life sciences and other fields. Also, see this link for conducting a lit review exclusively within Web of Science.

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Open Access

Study Protocol

Health professionals’ attitudes towards traditional healing for mental illness: A systematic review protocol

Roles Conceptualization, Methodology, Writing – original draft, Writing – review & editing

* E-mail: [email protected]

Affiliations Faculty of Medicine and Health, School of Health, University of New England, Armidale, NSW, Australia, Department of Psychiatry, College of Medicine and Health Sciences, Injibara University, Injibara, Ethiopia

Roles Supervision, Validation, Visualization, Writing – review & editing

Affiliation Faculty of Medicine and Health, School of Health, University of New England, Armidale, NSW, Australia

• Alemayehu Molla Wollie, 
• Kim Usher, 
• Reshin Maharaj, 
• Md Shahidul Islam

• Published: September 9, 2024
• https://doi.org/10.1371/journal.pone.0310255
• Peer Review
• Reader Comments

Mental illness is a global problem that receives less attention, particularly in developing countries. Integrating modern treatment with traditional healing approaches has been proposed as one way to address mental health problems, especially in developing countries. Despite health professionals’ participation in traditional healing being crucial to integrative approaches, their participation is limited to date. This review protocol is designed to explore the attitudes of health professionals towards traditional healing practices in mental health services.

The review will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Searching databases, including PubMed/Medline, PsychINFO, EMBASE, Scopus, and the Web of sciences will be conducted. Additionally, Google and Google Scholar will be searched for other information, including grey literature. Moreover, a manual search of identified articles’ reference lists will also be conducted to help ensure all potential papers are included in the review. Qualitative, quantitative, and mixed study methods published in English between January 2014 and April 2024 will be included. The qualities of the included studies will be assessed using the Mixed Methods Appraisal Tool (MMAT) Version 2018. A mixed-method synthesis will be used to synthesis the results.

It is crucial for healthcare professionals to provide culturally sensitive care to empower people to manage their health. This systematic review will summarize the attitudes of health professionals towards the adoption and delivery of traditional healing approaches to people experiencing mental illness. Therefore, the findings of this review will support integration between traditional healers and modern mental health practitioners for the treatment of mental illness.

Trial registration

Protocol registration number: CRD42024535136 .

Citation: Wollie AM, Usher K, Maharaj R, Islam MS (2024) Health professionals’ attitudes towards traditional healing for mental illness: A systematic review protocol. PLoS ONE 19(9): e0310255. https://doi.org/10.1371/journal.pone.0310255

Editor: Madhulika Sahoo, Kalahandi University, INDIA

Received: May 8, 2024; Accepted: August 27, 2024; Published: September 9, 2024

Copyright: © 2024 Wollie et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All data are in the manuscript.

Funding: The author(s) received no specific funding for this work.

Competing interests: The authors have declared that co competing interest exists.

Mental health is the overall wellbeing and functioning of an individual, family, and community [ 1 , 2 ]. It is “a state of wellbeing in which the individual realizes his or her own abilities, is able to contribute to his or her environment, copes with the normal stress of life, works fruitfully, and is able to cooperate with others [ 3 ].” In contrast, mental illness has a substantial impact on a person’s feelings, thoughts, behaviour, and social interactions [ 4 , 5 ]. It is influenced by numerous factors, including psychological, physical, social, cultural, and spiritual [ 6 , 7 ].

Currently, mental illness is a major public health burden and accounts for 32.4% of years lived with disability worldwide [ 8 ]. Even though mental health issues are a global health concern, they are highly prevalent in low-income countries [ 9 , 10 ]. Developing nations have fewer health professionals [ 11 ], resulting in a treatment gap for people with mental illnesses in these countries [ 12 ]. Furthermore, negative attitudes, stigma, limited resources, and low priority are reasons for the high magnitude of mental illness, in addition to a shortage of health professionals [ 13 – 16 ].

People with mental health issues often seek care from indigenous or traditional healers [ 17 – 19 ]. Traditional healing practices include but are not limited to a set of beliefs that use culturally accepted spiritual treatments and plant products [ 20 ]. Traditional healers form a major part of the mental health workforce in developing countries [ 21 ]. Nearly 80% of people from Africa seek medical attention from traditional healers [ 21 ], largely because traditional healers provide culturally and socially accepted care for individuals and communities. This is the preferred treatment approach for most people due to its perceived effectiveness, affordability, and accessibility within communities [ 22 – 24 ]. In order to close the significant treatment gap in low-and middle-income countries, “the World Health Organization’s (WHO) 2003–2020 Mental Health Action Plan recommended that government health programs incorporate traditional healers as treatment resources [ 25 ].”

Studies indicate that traditional healers can offer efficacious therapies that may be beneficial for prevalent mental illnesses such as depression and anxiety [ 26 , 27 ]. Healers usually come from extended family branches with experience providing care like counselling, bible interpretation, and using prayer aids such as holy water and oil for treatment [ 27 , 28 ]. They either obtain experience through on-the-job training or apply their practices through ancestors who serve as mediators by providing access to spiritual guidance and power [ 15 , 29 , 30 ].

Despite the fact that traditional healing approaches are practiced by large groups of people, particularly in low-income countries, modern health professionals tend to differ in their opinions about this approach [ 31 , 32 ]. Studies indicate that some health professionals hold a positive view of traditional healing modalities [ 33 ], while many others express doubt about the effectiveness of traditional treatments. Furthermore, there is a negative attitude among health professionals regarding the integration of traditional healing with biomedical therapies [ 34 , 35 ]. Traditional healers are known to consult with modern health professionals when faced with problems beyond their ability to treat, but it is not common for biomedical professionals to refer back to healers [ 27 ]. This is often due to their negative attitudes toward traditional healing practices, including the belief that traditional healers do not incorporate a human right approach and/or compassionate care when dealing with people with mental health problems [ 35 , 36 ]. Their negative attitudes have a detrimental effect on the WHO’s recommended collaboration of biomedical treatment and traditional healing to close the treatment gap in low and middle-income countries because cooperation between the two needs mutual respect and recognition. In addition to providing biological therapies, it is good to emphasize spiritual and cultural approaches for mental illness since mental illness is due to multidimensional factors like spiritual, social, psychological, and physical. Moreover, it is crucial for healthcare providers to understand their patients’ cultural beliefs and practices in order to manage and counsel them appropriately [ 34 ] and empower them towards healthful healing. There is no summarized research regarding the attitudes of health professionals toward traditional healing approaches for mental illness, despite the existence of numerous singe studies. Therefor, this review protocol is aimed to explore the summarized evidences on health care providers’ attitudes toward traditional healing for mental illness, and this will be crucial in developing appropriate guidelines for holistic treatment.

Research question

What are the health professionals’ attitudes towards traditional healing for mental illness?

Methods and materials

The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) 2020 guidelines will be used to conduct this review [ 37 ]. This protocol is also prepared in accordance with the PRISAM-Protocol guidelines (Supporting Information). Primary studies conducted using quantitative, quantitative, and mixed-methods will be included. The review protocol is registered with the International Prospective Register of Systematic Reviews (PROSPERO) with a registration number of CRD42014535136.

Eligibility criteria

The eligibility assessment format will be used to select articles to be included in the systematic review. Globally published original articles focusing on health professionals’ attitude and/or perception towards traditional healing of mental illness will be considered. Qualitative, quantitative, and mixed-method studies will be considered without restrictions in their study design. Studies published in English between January 2014 and April 2024 will be considered to summarize contemporary evidence on the topic. Conference summaries, reviews, dissertations, case studies, governmental and non-government reports, and letters will be excluded from the study.

Searching strategy

A literature search of databases such as PubMed/Medline, PsychINFO, EMBASE, Scopus, and the Web of Sciences will be conducted. The key terms will be searched by connecting Boolean operators OR/AND to specifically address published studies. Searching words will be (attitude) OR (perception) OR (belief) OR (opinion) OR (view) AND (health professionals) OR (health practitioners) OR (health personnel) OR (nurses) OR (medical doctors) OR (psychiatrist) OR (psychologist) AND (traditional healing) OR (traditional medicine) OR (herbal medicine) OR (indigenous treatment) OR (spiritual therapy) OR (religious healing) AND (mental illness) OR (mental disorder) OR (mental health) OR (psychological distress) OR (psychiatric disorder). In addition to database and manual searches, we will use references to articles obtained from the database to filter the remaining studies. Database searching and the initial screening process will be finalized in consultation with a senior health librarian from the University of New England (UNE) Dixon Library and other authors.

An example of a search strategy for Scopus ( (ALL ("health professional") OR TITLE-ABS-KEY ("health personnel") OR TITLE-ABS-KEY ("medical doctor") OR TITLE-ABS-KEY ("medical practitioner") OR TITLE-ABS-KEY (nurse) OR TITLE-ABS-KEY (psychiatrist) OR TITLE-ABS-KEY (psychologist) ) ) AND ( (ALL (perception) OR TITLE-ABS-KEY (attitude) OR TITLE-ABS-KEY (belief) OR TITLE-ABS-KEY (view) OR TITLE-ABS-KEY (opinion) ) ) AND ( (ALL ("traditional healing") OR TITLE-ABS-KEY ("traditional medicine") OR TITLE-ABS-KEY ("indigenous treatment") OR TITLE-ABS-KEY ("spiritual therapy") OR TITLE-ABS-KEY ("religious healing") OR TITLE-ABS-KEY ("herbal medicine") ) ) AND ( (ALL ("mental illness") OR TITLE-ABS-KEY ("mental disorder") OR TITLE-ABS-KEY ("mental health") OR TITLE-ABS-KEY ("psychiatric disorder") OR TITLE-ABS-KEY ("psychological distress") ) ) AND PUBYEAR > 2013 AND PUBYEAR < 2025 AND (LIMIT-TO (DOCTYPE, "ar") ) AND (LIMIT-TO (LANGUAGE, "English") )

Study selection process

PRISMA (preferred reporting items for the systematic review and meta-analysis) guidelines [ 37 ] will be followed to ensure the quality and transparency of the review process. After critically searching articles from databases, we will start the selection process by importing all records to an Endnote library. Duplicates will be detected and removed automatically. At the beginning, the selection process will be carried out by the first author (AMW), and it will be checked by one of the co-authors (KU, RM, and SI). The reviewer will evaluate article titles and abstracts for relevance, keeping those that are relevant to the outcome variable attitudes, and/or perceptions of health professionals towards traditional healing. The full texts of possible relevant papers will then be screened for eligibility. Any disagreements will be handled through a discussion to finalize the selection of the papers.

Data extraction or collection process

With the use of a predetermined, uniform data extraction structure, the first author will extract important data, and then it will be confirmed by another author. Any significant differences will be discussed, and if a consensus cannot be reached, a third author will adjudicate on the decision. The first author’s name, the year of publication, the country where the study is conducted, the methodology used, the health professional type, the data collection and analysis method, the major findings, and the conclusions will be included in the standardized data extraction form.

Quality assessment

Each study’s methodological quality and bias risk will be assessed to determine the validity of the findings. The qualities of the included articles will be assessed using the Mixed Methods Appraisal Tool (MMAT) Version 2018 Checklist [ 38 ]. This tool is designed to assess the methodological qualities of different types of studies, like qualitative, quantitative, and mixed studies. The differences in quality evaluation scores will be resolved by through discussion within a team.

Data synthesis

An integrated mixed-method synthesis technique will be used to summarize all quantitative, qualitative, and mixed-method data in one combined synthesis [ 39 ]. Quantitative data will be described qualitatively to facilitate integration with qualitative data. The overall nature of the articles will be presented in a table. Themes and subthemes will be formulated based on the data generated. All the data will be analysed and reported as a narrative summary. To minimize bias, the research team will thoroughly evaluate and discuss the entire process, and any disagreements will be resolved through discussion.

The review will be conducted to summarize the attitudes of health professionals towards traditional healing approaches for mental illness in a global context. Even though independent studies have been undertaken on health professionals’ attitudes and/or perceptions towards traditional healing, there is no globally summarized general evidence on the topic. Some previous studies present opposing evidence on the attitudes of health professionals towards traditional healing practices. Even if some health professionals encourage traditional methods, there are other studies that show negative attitudes of health professionals towards traditional healing [ 34 , 35 ]. Traditional healing practices are considered appropriate options for mental illness, particularly in low-income countries where there is a scarcity of modern mental health professionals [ 21 ]. Most people with mental health problems seek these treatments because they provide culturally and socially accepted care for individuals and the community [ 22 – 24 ]. But there is limited collaboration between modern treatment and traditional healing. Therefore, this review will summarize all the literature and clearly show the positions of health professionals toward traditional healing approaches. The findings of this review will be important in developing directions for governmental organizations and other concerned bodies to strengthen communication and integration of traditional healing with biomedical treatment options for mental illness.

Expected limitations

This systematic review has the limitation of excluding articles that are not published in English. In addition, the exclusion of conference reports, letter, short communications, and review articles may be a reason to miss important data.

Publication status

This protocol is prepared for the ongoing systematic review of articles entitled “The health professionals’ attitude towards traditional healing approaches to mental illness.” If there is any change during the review, an updated version will be published with a final systematic review.

Supporting information

S1 checklist. prisma-protocol guidelines..

https://doi.org/10.1371/journal.pone.0310255.s001

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How to Conduct a Literature Review (Health Sciences and Beyond)

• What is a Literature Review?
• Developing a Research Question
• Selection Criteria

Choosing Search Terms

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• Organize Key Findings
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Connecting terms with AND requires all terms to appear in the same article.

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Keep in mind that search is not a linear process -- you will need to test and revise as you go. Terms that seem good may not find good results, or your topic may be too broad or too narrow.

If you would like assistance with your search, contact a librarian .

Before starting your database search, think about terms that can be used to describe the key concepts in your research question. Start your search with terms that you think make sense.  When you find citations that are highly relevant to your research, take a closer look at those records. Examine those records for two types of terms  that you can use in your search : subject headings  and keywords.

• Subject Heading : A single, assigned term that stands for a concept. For example, in PubMed, any paper that discusses acetylsalicylic  acid  would be assigned the Medical Subject Heading (MeSH) term aspirin . A search for the MeSH term  Aspirin  in PubMed should find papers written about aspirin  whether or not the word actually appears in the title or abstract.
• Keyword : Term used for a concept in everyday language. For example, if you need to find articles written about bedpans , the  Medical Subject Heading (MeSH)  term Toilet Facilities  in PubMed may be too broad. Just searching for bedpan OR bedpans  by typing this directly into the search box might work better.

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When you conduct your search, consider whether it makes sense to use keywords, subject headings, or both.

See "Documenting Your Search"  to learn how to keep track of useful terms.

Many databases allow you to filter your search. You can usually find filters are on the left-hand side of your results page . Based on your selection criteria , you may want to filter your results based on:

• Publication date range (e.g. last 10 years)
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• Article type (e.g. review, research report, etc.)
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If you're searching different databases for information, keep in mind that you may need to adjust your search terms for each database. For instance, the equivalent subject heading for  " Heart, Artificial" in  PubMed is "Heart, Mechanical" in CINAHL. Additionally, because CINAHL is an allied health and nursing database, you will find specialized subject headings such as "Toileting" in CINAHL that you won't find in PubMed.

Keywords are more likely to stay consistent across databases.

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• Last Updated: Mar 15, 2024 12:22 PM
• URL: https://guides.library.vcu.edu/health-sciences-lit-review

Cadmium Associated Preeclampsia: A Systematic Literature Review of Pregnancy and Birth Outcomes

• Published: 10 September 2024

Cite this article

• Fatima Sardar 1 ,
• Yuhaniza Shafinie Kamsani 1 , 2 ,
• Fathi Ramly 1 , 3 ,
• Nor Ashikin Mohamed Noor Khan 1 , 2 ,
• Razia Sardar 1 &
• Anisa Aishah Aminuddin 1 , 3  

28 Accesses

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Preeclampsia (PE), caused by multiple factors, is one of the most serious complications of pregnancy. Cadmium (Cd) is a heavy metal environmental pollutant, reproductive toxicant, and endocrine disruptor, which can increase the risk of PE. Cd toxicity due to occupational, diet, and environmental factors has worsened the risk. Studies showed elevated Cd concentration in maternal blood and placenta of PE women. However, the implicit association between Cd associated PE is still not highlighted. We systematically reviewed Cd-associated PE and its effect on pregnancy and birth outcomes. Based on “Preferred reporting items for systematic reviews and meta-analyses (PRISMA)” guidelines, eighty-six studies were identified by PubMed, Web of Science (WOS), and Scopus databases. Publications were included until October 2023 and articles screened based on our inclusion criteria. Our study identified that the exposure of controlled and uncontrolled Cd induces PE, which negatively affects pregnancy and birth outcomes. Given the serious nature of this finding, Cd is a potential adverse agent that impacts pregnancy and future neonatal health. Further comprehensive studies covering the whole trimesters of pregnancy and neonatal developments are warranted. Data on the molecular mechanisms behind Cd-induced PE is also essential for potential preventive, diagnostic, or therapeutic targets.

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Maternal Exposure to Cadmium and Fetal Growth: a Systematic Review and Meta-Analysis

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Acknowledgements

This study has been conducted in the framework of the research activities of the projects funded by University Technology Mara (UiTM) under grants: 600-UiTMSEL (PI.5/4) (023/2022) and 600-TNCPI 5/3/DDF (MEDIC) (004/2021). The authors are grateful to University Technology Mara (UiTM) for supporting this research. The authors also appreciate and acknowledge the valuable time of the Editor and the reviewers.

This study has been conducted in the framework of the research activities of the projects funded by University Technology Mara (UiTM) under grants: 600-UiTMSEL (PI.5/4) (023/2022) and 600-TNCPI 5/3/DDF (MEDIC) (004/2021).

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Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia

Fatima Sardar, Yuhaniza Shafinie Kamsani, Fathi Ramly, Nor Ashikin Mohamed Noor Khan, Razia Sardar & Anisa Aishah Aminuddin

Maternofetal and Embryo (MatE) Research Group, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia

Yuhaniza Shafinie Kamsani & Nor Ashikin Mohamed Noor Khan

Department of Obstetrics & Gynaecology, Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia

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The authors FS and RS identified and evaluated each study separately. Based on seven domains (mentioned in Fig.  2 ), the studies were categorized into “low risk”, “unclear”, and “high risk” by FS and RS and then checked by YSK, FR, and AAA. The detailed review evaluation of the selected studies was made by FS and RS. The results were discussed with four other authors (YSK, FR, AAA, and NAMK). These four authors checked and verified the findings.

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Sardar, F., Kamsani, Y.S., Ramly, F. et al. Cadmium Associated Preeclampsia: A Systematic Literature Review of Pregnancy and Birth Outcomes. Biol Trace Elem Res (2024). https://doi.org/10.1007/s12011-024-04364-5

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DOI : https://doi.org/10.1007/s12011-024-04364-5

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Lau F, Kuziemsky C, editors. Handbook of eHealth Evaluation: An Evidence-based Approach [Internet]. Victoria (BC): University of Victoria; 2017 Feb 27.

Handbook of eHealth Evaluation: An Evidence-based Approach [Internet].

Chapter 9 methods for literature reviews.

Guy Paré and Spyros Kitsiou .

9.1. Introduction

Literature reviews play a critical role in scholarship because science remains, first and foremost, a cumulative endeavour ( vom Brocke et al., 2009 ). As in any academic discipline, rigorous knowledge syntheses are becoming indispensable in keeping up with an exponentially growing eHealth literature, assisting practitioners, academics, and graduate students in finding, evaluating, and synthesizing the contents of many empirical and conceptual papers. Among other methods, literature reviews are essential for: (a) identifying what has been written on a subject or topic; (b) determining the extent to which a specific research area reveals any interpretable trends or patterns; (c) aggregating empirical findings related to a narrow research question to support evidence-based practice; (d) generating new frameworks and theories; and (e) identifying topics or questions requiring more investigation ( Paré, Trudel, Jaana, & Kitsiou, 2015 ).

Literature reviews can take two major forms. The most prevalent one is the “literature review” or “background” section within a journal paper or a chapter in a graduate thesis. This section synthesizes the extant literature and usually identifies the gaps in knowledge that the empirical study addresses ( Sylvester, Tate, & Johnstone, 2013 ). It may also provide a theoretical foundation for the proposed study, substantiate the presence of the research problem, justify the research as one that contributes something new to the cumulated knowledge, or validate the methods and approaches for the proposed study ( Hart, 1998 ; Levy & Ellis, 2006 ).

The second form of literature review, which is the focus of this chapter, constitutes an original and valuable work of research in and of itself ( Paré et al., 2015 ). Rather than providing a base for a researcher’s own work, it creates a solid starting point for all members of the community interested in a particular area or topic ( Mulrow, 1987 ). The so-called “review article” is a journal-length paper which has an overarching purpose to synthesize the literature in a field, without collecting or analyzing any primary data ( Green, Johnson, & Adams, 2006 ).

When appropriately conducted, review articles represent powerful information sources for practitioners looking for state-of-the art evidence to guide their decision-making and work practices ( Paré et al., 2015 ). Further, high-quality reviews become frequently cited pieces of work which researchers seek out as a first clear outline of the literature when undertaking empirical studies ( Cooper, 1988 ; Rowe, 2014 ). Scholars who track and gauge the impact of articles have found that review papers are cited and downloaded more often than any other type of published article ( Cronin, Ryan, & Coughlan, 2008 ; Montori, Wilczynski, Morgan, Haynes, & Hedges, 2003 ; Patsopoulos, Analatos, & Ioannidis, 2005 ). The reason for their popularity may be the fact that reading the review enables one to have an overview, if not a detailed knowledge of the area in question, as well as references to the most useful primary sources ( Cronin et al., 2008 ). Although they are not easy to conduct, the commitment to complete a review article provides a tremendous service to one’s academic community ( Paré et al., 2015 ; Petticrew & Roberts, 2006 ). Most, if not all, peer-reviewed journals in the fields of medical informatics publish review articles of some type.

The main objectives of this chapter are fourfold: (a) to provide an overview of the major steps and activities involved in conducting a stand-alone literature review; (b) to describe and contrast the different types of review articles that can contribute to the eHealth knowledge base; (c) to illustrate each review type with one or two examples from the eHealth literature; and (d) to provide a series of recommendations for prospective authors of review articles in this domain.

9.2. Overview of the Literature Review Process and Steps

As explained in Templier and Paré (2015) , there are six generic steps involved in conducting a review article:

• formulating the research question(s) and objective(s),
• searching the extant literature,
• screening for inclusion,
• assessing the quality of primary studies,
• extracting data, and
• analyzing data.

Although these steps are presented here in sequential order, one must keep in mind that the review process can be iterative and that many activities can be initiated during the planning stage and later refined during subsequent phases ( Finfgeld-Connett & Johnson, 2013 ; Kitchenham & Charters, 2007 ).

Formulating the research question(s) and objective(s): As a first step, members of the review team must appropriately justify the need for the review itself ( Petticrew & Roberts, 2006 ), identify the review’s main objective(s) ( Okoli & Schabram, 2010 ), and define the concepts or variables at the heart of their synthesis ( Cooper & Hedges, 2009 ; Webster & Watson, 2002 ). Importantly, they also need to articulate the research question(s) they propose to investigate ( Kitchenham & Charters, 2007 ). In this regard, we concur with Jesson, Matheson, and Lacey (2011) that clearly articulated research questions are key ingredients that guide the entire review methodology; they underscore the type of information that is needed, inform the search for and selection of relevant literature, and guide or orient the subsequent analysis. Searching the extant literature: The next step consists of searching the literature and making decisions about the suitability of material to be considered in the review ( Cooper, 1988 ). There exist three main coverage strategies. First, exhaustive coverage means an effort is made to be as comprehensive as possible in order to ensure that all relevant studies, published and unpublished, are included in the review and, thus, conclusions are based on this all-inclusive knowledge base. The second type of coverage consists of presenting materials that are representative of most other works in a given field or area. Often authors who adopt this strategy will search for relevant articles in a small number of top-tier journals in a field ( Paré et al., 2015 ). In the third strategy, the review team concentrates on prior works that have been central or pivotal to a particular topic. This may include empirical studies or conceptual papers that initiated a line of investigation, changed how problems or questions were framed, introduced new methods or concepts, or engendered important debate ( Cooper, 1988 ). Screening for inclusion: The following step consists of evaluating the applicability of the material identified in the preceding step ( Levy & Ellis, 2006 ; vom Brocke et al., 2009 ). Once a group of potential studies has been identified, members of the review team must screen them to determine their relevance ( Petticrew & Roberts, 2006 ). A set of predetermined rules provides a basis for including or excluding certain studies. This exercise requires a significant investment on the part of researchers, who must ensure enhanced objectivity and avoid biases or mistakes. As discussed later in this chapter, for certain types of reviews there must be at least two independent reviewers involved in the screening process and a procedure to resolve disagreements must also be in place ( Liberati et al., 2009 ; Shea et al., 2009 ). Assessing the quality of primary studies: In addition to screening material for inclusion, members of the review team may need to assess the scientific quality of the selected studies, that is, appraise the rigour of the research design and methods. Such formal assessment, which is usually conducted independently by at least two coders, helps members of the review team refine which studies to include in the final sample, determine whether or not the differences in quality may affect their conclusions, or guide how they analyze the data and interpret the findings ( Petticrew & Roberts, 2006 ). Ascribing quality scores to each primary study or considering through domain-based evaluations which study components have or have not been designed and executed appropriately makes it possible to reflect on the extent to which the selected study addresses possible biases and maximizes validity ( Shea et al., 2009 ). Extracting data: The following step involves gathering or extracting applicable information from each primary study included in the sample and deciding what is relevant to the problem of interest ( Cooper & Hedges, 2009 ). Indeed, the type of data that should be recorded mainly depends on the initial research questions ( Okoli & Schabram, 2010 ). However, important information may also be gathered about how, when, where and by whom the primary study was conducted, the research design and methods, or qualitative/quantitative results ( Cooper & Hedges, 2009 ). Analyzing and synthesizing data : As a final step, members of the review team must collate, summarize, aggregate, organize, and compare the evidence extracted from the included studies. The extracted data must be presented in a meaningful way that suggests a new contribution to the extant literature ( Jesson et al., 2011 ). Webster and Watson (2002) warn researchers that literature reviews should be much more than lists of papers and should provide a coherent lens to make sense of extant knowledge on a given topic. There exist several methods and techniques for synthesizing quantitative (e.g., frequency analysis, meta-analysis) and qualitative (e.g., grounded theory, narrative analysis, meta-ethnography) evidence ( Dixon-Woods, Agarwal, Jones, Young, & Sutton, 2005 ; Thomas & Harden, 2008 ).

9.3. Types of Review Articles and Brief Illustrations

EHealth researchers have at their disposal a number of approaches and methods for making sense out of existing literature, all with the purpose of casting current research findings into historical contexts or explaining contradictions that might exist among a set of primary research studies conducted on a particular topic. Our classification scheme is largely inspired from Paré and colleagues’ (2015) typology. Below we present and illustrate those review types that we feel are central to the growth and development of the eHealth domain.

9.3.1. Narrative Reviews

The narrative review is the “traditional” way of reviewing the extant literature and is skewed towards a qualitative interpretation of prior knowledge ( Sylvester et al., 2013 ). Put simply, a narrative review attempts to summarize or synthesize what has been written on a particular topic but does not seek generalization or cumulative knowledge from what is reviewed ( Davies, 2000 ; Green et al., 2006 ). Instead, the review team often undertakes the task of accumulating and synthesizing the literature to demonstrate the value of a particular point of view ( Baumeister & Leary, 1997 ). As such, reviewers may selectively ignore or limit the attention paid to certain studies in order to make a point. In this rather unsystematic approach, the selection of information from primary articles is subjective, lacks explicit criteria for inclusion and can lead to biased interpretations or inferences ( Green et al., 2006 ). There are several narrative reviews in the particular eHealth domain, as in all fields, which follow such an unstructured approach ( Silva et al., 2015 ; Paul et al., 2015 ).

Despite these criticisms, this type of review can be very useful in gathering together a volume of literature in a specific subject area and synthesizing it. As mentioned above, its primary purpose is to provide the reader with a comprehensive background for understanding current knowledge and highlighting the significance of new research ( Cronin et al., 2008 ). Faculty like to use narrative reviews in the classroom because they are often more up to date than textbooks, provide a single source for students to reference, and expose students to peer-reviewed literature ( Green et al., 2006 ). For researchers, narrative reviews can inspire research ideas by identifying gaps or inconsistencies in a body of knowledge, thus helping researchers to determine research questions or formulate hypotheses. Importantly, narrative reviews can also be used as educational articles to bring practitioners up to date with certain topics of issues ( Green et al., 2006 ).

Recently, there have been several efforts to introduce more rigour in narrative reviews that will elucidate common pitfalls and bring changes into their publication standards. Information systems researchers, among others, have contributed to advancing knowledge on how to structure a “traditional” review. For instance, Levy and Ellis (2006) proposed a generic framework for conducting such reviews. Their model follows the systematic data processing approach comprised of three steps, namely: (a) literature search and screening; (b) data extraction and analysis; and (c) writing the literature review. They provide detailed and very helpful instructions on how to conduct each step of the review process. As another methodological contribution, vom Brocke et al. (2009) offered a series of guidelines for conducting literature reviews, with a particular focus on how to search and extract the relevant body of knowledge. Last, Bandara, Miskon, and Fielt (2011) proposed a structured, predefined and tool-supported method to identify primary studies within a feasible scope, extract relevant content from identified articles, synthesize and analyze the findings, and effectively write and present the results of the literature review. We highly recommend that prospective authors of narrative reviews consult these useful sources before embarking on their work.

Darlow and Wen (2015) provide a good example of a highly structured narrative review in the eHealth field. These authors synthesized published articles that describe the development process of mobile health (m-health) interventions for patients’ cancer care self-management. As in most narrative reviews, the scope of the research questions being investigated is broad: (a) how development of these systems are carried out; (b) which methods are used to investigate these systems; and (c) what conclusions can be drawn as a result of the development of these systems. To provide clear answers to these questions, a literature search was conducted on six electronic databases and Google Scholar . The search was performed using several terms and free text words, combining them in an appropriate manner. Four inclusion and three exclusion criteria were utilized during the screening process. Both authors independently reviewed each of the identified articles to determine eligibility and extract study information. A flow diagram shows the number of studies identified, screened, and included or excluded at each stage of study selection. In terms of contributions, this review provides a series of practical recommendations for m-health intervention development.

9.3.2. Descriptive or Mapping Reviews

The primary goal of a descriptive review is to determine the extent to which a body of knowledge in a particular research topic reveals any interpretable pattern or trend with respect to pre-existing propositions, theories, methodologies or findings ( King & He, 2005 ; Paré et al., 2015 ). In contrast with narrative reviews, descriptive reviews follow a systematic and transparent procedure, including searching, screening and classifying studies ( Petersen, Vakkalanka, & Kuzniarz, 2015 ). Indeed, structured search methods are used to form a representative sample of a larger group of published works ( Paré et al., 2015 ). Further, authors of descriptive reviews extract from each study certain characteristics of interest, such as publication year, research methods, data collection techniques, and direction or strength of research outcomes (e.g., positive, negative, or non-significant) in the form of frequency analysis to produce quantitative results ( Sylvester et al., 2013 ). In essence, each study included in a descriptive review is treated as the unit of analysis and the published literature as a whole provides a database from which the authors attempt to identify any interpretable trends or draw overall conclusions about the merits of existing conceptualizations, propositions, methods or findings ( Paré et al., 2015 ). In doing so, a descriptive review may claim that its findings represent the state of the art in a particular domain ( King & He, 2005 ).

In the fields of health sciences and medical informatics, reviews that focus on examining the range, nature and evolution of a topic area are described by Anderson, Allen, Peckham, and Goodwin (2008) as mapping reviews . Like descriptive reviews, the research questions are generic and usually relate to publication patterns and trends. There is no preconceived plan to systematically review all of the literature although this can be done. Instead, researchers often present studies that are representative of most works published in a particular area and they consider a specific time frame to be mapped.

An example of this approach in the eHealth domain is offered by DeShazo, Lavallie, and Wolf (2009). The purpose of this descriptive or mapping review was to characterize publication trends in the medical informatics literature over a 20-year period (1987 to 2006). To achieve this ambitious objective, the authors performed a bibliometric analysis of medical informatics citations indexed in medline using publication trends, journal frequencies, impact factors, Medical Subject Headings (MeSH) term frequencies, and characteristics of citations. Findings revealed that there were over 77,000 medical informatics articles published during the covered period in numerous journals and that the average annual growth rate was 12%. The MeSH term analysis also suggested a strong interdisciplinary trend. Finally, average impact scores increased over time with two notable growth periods. Overall, patterns in research outputs that seem to characterize the historic trends and current components of the field of medical informatics suggest it may be a maturing discipline (DeShazo et al., 2009).

9.3.3. Scoping Reviews

Scoping reviews attempt to provide an initial indication of the potential size and nature of the extant literature on an emergent topic (Arksey & O’Malley, 2005; Daudt, van Mossel, & Scott, 2013 ; Levac, Colquhoun, & O’Brien, 2010). A scoping review may be conducted to examine the extent, range and nature of research activities in a particular area, determine the value of undertaking a full systematic review (discussed next), or identify research gaps in the extant literature ( Paré et al., 2015 ). In line with their main objective, scoping reviews usually conclude with the presentation of a detailed research agenda for future works along with potential implications for both practice and research.

Unlike narrative and descriptive reviews, the whole point of scoping the field is to be as comprehensive as possible, including grey literature (Arksey & O’Malley, 2005). Inclusion and exclusion criteria must be established to help researchers eliminate studies that are not aligned with the research questions. It is also recommended that at least two independent coders review abstracts yielded from the search strategy and then the full articles for study selection ( Daudt et al., 2013 ). The synthesized evidence from content or thematic analysis is relatively easy to present in tabular form (Arksey & O’Malley, 2005; Thomas & Harden, 2008 ).

One of the most highly cited scoping reviews in the eHealth domain was published by Archer, Fevrier-Thomas, Lokker, McKibbon, and Straus (2011) . These authors reviewed the existing literature on personal health record ( phr ) systems including design, functionality, implementation, applications, outcomes, and benefits. Seven databases were searched from 1985 to March 2010. Several search terms relating to phr s were used during this process. Two authors independently screened titles and abstracts to determine inclusion status. A second screen of full-text articles, again by two independent members of the research team, ensured that the studies described phr s. All in all, 130 articles met the criteria and their data were extracted manually into a database. The authors concluded that although there is a large amount of survey, observational, cohort/panel, and anecdotal evidence of phr benefits and satisfaction for patients, more research is needed to evaluate the results of phr implementations. Their in-depth analysis of the literature signalled that there is little solid evidence from randomized controlled trials or other studies through the use of phr s. Hence, they suggested that more research is needed that addresses the current lack of understanding of optimal functionality and usability of these systems, and how they can play a beneficial role in supporting patient self-management ( Archer et al., 2011 ).

9.3.4. Forms of Aggregative Reviews

Healthcare providers, practitioners, and policy-makers are nowadays overwhelmed with large volumes of information, including research-based evidence from numerous clinical trials and evaluation studies, assessing the effectiveness of health information technologies and interventions ( Ammenwerth & de Keizer, 2004 ; Deshazo et al., 2009 ). It is unrealistic to expect that all these disparate actors will have the time, skills, and necessary resources to identify the available evidence in the area of their expertise and consider it when making decisions. Systematic reviews that involve the rigorous application of scientific strategies aimed at limiting subjectivity and bias (i.e., systematic and random errors) can respond to this challenge.

Systematic reviews attempt to aggregate, appraise, and synthesize in a single source all empirical evidence that meet a set of previously specified eligibility criteria in order to answer a clearly formulated and often narrow research question on a particular topic of interest to support evidence-based practice ( Liberati et al., 2009 ). They adhere closely to explicit scientific principles ( Liberati et al., 2009 ) and rigorous methodological guidelines (Higgins & Green, 2008) aimed at reducing random and systematic errors that can lead to deviations from the truth in results or inferences. The use of explicit methods allows systematic reviews to aggregate a large body of research evidence, assess whether effects or relationships are in the same direction and of the same general magnitude, explain possible inconsistencies between study results, and determine the strength of the overall evidence for every outcome of interest based on the quality of included studies and the general consistency among them ( Cook, Mulrow, & Haynes, 1997 ). The main procedures of a systematic review involve:

• Formulating a review question and developing a search strategy based on explicit inclusion criteria for the identification of eligible studies (usually described in the context of a detailed review protocol).
• Searching for eligible studies using multiple databases and information sources, including grey literature sources, without any language restrictions.
• Selecting studies, extracting data, and assessing risk of bias in a duplicate manner using two independent reviewers to avoid random or systematic errors in the process.
• Analyzing data using quantitative or qualitative methods.
• Presenting results in summary of findings tables.
• Interpreting results and drawing conclusions.

Many systematic reviews, but not all, use statistical methods to combine the results of independent studies into a single quantitative estimate or summary effect size. Known as meta-analyses , these reviews use specific data extraction and statistical techniques (e.g., network, frequentist, or Bayesian meta-analyses) to calculate from each study by outcome of interest an effect size along with a confidence interval that reflects the degree of uncertainty behind the point estimate of effect ( Borenstein, Hedges, Higgins, & Rothstein, 2009 ; Deeks, Higgins, & Altman, 2008 ). Subsequently, they use fixed or random-effects analysis models to combine the results of the included studies, assess statistical heterogeneity, and calculate a weighted average of the effect estimates from the different studies, taking into account their sample sizes. The summary effect size is a value that reflects the average magnitude of the intervention effect for a particular outcome of interest or, more generally, the strength of a relationship between two variables across all studies included in the systematic review. By statistically combining data from multiple studies, meta-analyses can create more precise and reliable estimates of intervention effects than those derived from individual studies alone, when these are examined independently as discrete sources of information.

The review by Gurol-Urganci, de Jongh, Vodopivec-Jamsek, Atun, and Car (2013) on the effects of mobile phone messaging reminders for attendance at healthcare appointments is an illustrative example of a high-quality systematic review with meta-analysis. Missed appointments are a major cause of inefficiency in healthcare delivery with substantial monetary costs to health systems. These authors sought to assess whether mobile phone-based appointment reminders delivered through Short Message Service ( sms ) or Multimedia Messaging Service ( mms ) are effective in improving rates of patient attendance and reducing overall costs. To this end, they conducted a comprehensive search on multiple databases using highly sensitive search strategies without language or publication-type restrictions to identify all rct s that are eligible for inclusion. In order to minimize the risk of omitting eligible studies not captured by the original search, they supplemented all electronic searches with manual screening of trial registers and references contained in the included studies. Study selection, data extraction, and risk of bias assessments were performed inde­­pen­dently by two coders using standardized methods to ensure consistency and to eliminate potential errors. Findings from eight rct s involving 6,615 participants were pooled into meta-analyses to calculate the magnitude of effects that mobile text message reminders have on the rate of attendance at healthcare appointments compared to no reminders and phone call reminders.

Meta-analyses are regarded as powerful tools for deriving meaningful conclusions. However, there are situations in which it is neither reasonable nor appropriate to pool studies together using meta-analytic methods simply because there is extensive clinical heterogeneity between the included studies or variation in measurement tools, comparisons, or outcomes of interest. In these cases, systematic reviews can use qualitative synthesis methods such as vote counting, content analysis, classification schemes and tabulations, as an alternative approach to narratively synthesize the results of the independent studies included in the review. This form of review is known as qualitative systematic review.

A rigorous example of one such review in the eHealth domain is presented by Mickan, Atherton, Roberts, Heneghan, and Tilson (2014) on the use of handheld computers by healthcare professionals and their impact on access to information and clinical decision-making. In line with the methodological guide­lines for systematic reviews, these authors: (a) developed and registered with prospero ( www.crd.york.ac.uk/ prospero / ) an a priori review protocol; (b) conducted comprehensive searches for eligible studies using multiple databases and other supplementary strategies (e.g., forward searches); and (c) subsequently carried out study selection, data extraction, and risk of bias assessments in a duplicate manner to eliminate potential errors in the review process. Heterogeneity between the included studies in terms of reported outcomes and measures precluded the use of meta-analytic methods. To this end, the authors resorted to using narrative analysis and synthesis to describe the effectiveness of handheld computers on accessing information for clinical knowledge, adherence to safety and clinical quality guidelines, and diagnostic decision-making.

In recent years, the number of systematic reviews in the field of health informatics has increased considerably. Systematic reviews with discordant findings can cause great confusion and make it difficult for decision-makers to interpret the review-level evidence ( Moher, 2013 ). Therefore, there is a growing need for appraisal and synthesis of prior systematic reviews to ensure that decision-making is constantly informed by the best available accumulated evidence. Umbrella reviews , also known as overviews of systematic reviews, are tertiary types of evidence synthesis that aim to accomplish this; that is, they aim to compare and contrast findings from multiple systematic reviews and meta-analyses ( Becker & Oxman, 2008 ). Umbrella reviews generally adhere to the same principles and rigorous methodological guidelines used in systematic reviews. However, the unit of analysis in umbrella reviews is the systematic review rather than the primary study ( Becker & Oxman, 2008 ). Unlike systematic reviews that have a narrow focus of inquiry, umbrella reviews focus on broader research topics for which there are several potential interventions ( Smith, Devane, Begley, & Clarke, 2011 ). A recent umbrella review on the effects of home telemonitoring interventions for patients with heart failure critically appraised, compared, and synthesized evidence from 15 systematic reviews to investigate which types of home telemonitoring technologies and forms of interventions are more effective in reducing mortality and hospital admissions ( Kitsiou, Paré, & Jaana, 2015 ).

9.3.5. Realist Reviews

Realist reviews are theory-driven interpretative reviews developed to inform, enhance, or supplement conventional systematic reviews by making sense of heterogeneous evidence about complex interventions applied in diverse contexts in a way that informs policy decision-making ( Greenhalgh, Wong, Westhorp, & Pawson, 2011 ). They originated from criticisms of positivist systematic reviews which centre on their “simplistic” underlying assumptions ( Oates, 2011 ). As explained above, systematic reviews seek to identify causation. Such logic is appropriate for fields like medicine and education where findings of randomized controlled trials can be aggregated to see whether a new treatment or intervention does improve outcomes. However, many argue that it is not possible to establish such direct causal links between interventions and outcomes in fields such as social policy, management, and information systems where for any intervention there is unlikely to be a regular or consistent outcome ( Oates, 2011 ; Pawson, 2006 ; Rousseau, Manning, & Denyer, 2008 ).

To circumvent these limitations, Pawson, Greenhalgh, Harvey, and Walshe (2005) have proposed a new approach for synthesizing knowledge that seeks to unpack the mechanism of how “complex interventions” work in particular contexts. The basic research question — what works? — which is usually associated with systematic reviews changes to: what is it about this intervention that works, for whom, in what circumstances, in what respects and why? Realist reviews have no particular preference for either quantitative or qualitative evidence. As a theory-building approach, a realist review usually starts by articulating likely underlying mechanisms and then scrutinizes available evidence to find out whether and where these mechanisms are applicable ( Shepperd et al., 2009 ). Primary studies found in the extant literature are viewed as case studies which can test and modify the initial theories ( Rousseau et al., 2008 ).

The main objective pursued in the realist review conducted by Otte-Trojel, de Bont, Rundall, and van de Klundert (2014) was to examine how patient portals contribute to health service delivery and patient outcomes. The specific goals were to investigate how outcomes are produced and, most importantly, how variations in outcomes can be explained. The research team started with an exploratory review of background documents and research studies to identify ways in which patient portals may contribute to health service delivery and patient outcomes. The authors identified six main ways which represent “educated guesses” to be tested against the data in the evaluation studies. These studies were identified through a formal and systematic search in four databases between 2003 and 2013. Two members of the research team selected the articles using a pre-established list of inclusion and exclusion criteria and following a two-step procedure. The authors then extracted data from the selected articles and created several tables, one for each outcome category. They organized information to bring forward those mechanisms where patient portals contribute to outcomes and the variation in outcomes across different contexts.

9.3.6. Critical Reviews

Lastly, critical reviews aim to provide a critical evaluation and interpretive analysis of existing literature on a particular topic of interest to reveal strengths, weaknesses, contradictions, controversies, inconsistencies, and/or other important issues with respect to theories, hypotheses, research methods or results ( Baumeister & Leary, 1997 ; Kirkevold, 1997 ). Unlike other review types, critical reviews attempt to take a reflective account of the research that has been done in a particular area of interest, and assess its credibility by using appraisal instruments or critical interpretive methods. In this way, critical reviews attempt to constructively inform other scholars about the weaknesses of prior research and strengthen knowledge development by giving focus and direction to studies for further improvement ( Kirkevold, 1997 ).

Kitsiou, Paré, and Jaana (2013) provide an example of a critical review that assessed the methodological quality of prior systematic reviews of home telemonitoring studies for chronic patients. The authors conducted a comprehensive search on multiple databases to identify eligible reviews and subsequently used a validated instrument to conduct an in-depth quality appraisal. Results indicate that the majority of systematic reviews in this particular area suffer from important methodological flaws and biases that impair their internal validity and limit their usefulness for clinical and decision-making purposes. To this end, they provide a number of recommendations to strengthen knowledge development towards improving the design and execution of future reviews on home telemonitoring.

9.4. Summary

Table 9.1 outlines the main types of literature reviews that were described in the previous sub-sections and summarizes the main characteristics that distinguish one review type from another. It also includes key references to methodological guidelines and useful sources that can be used by eHealth scholars and researchers for planning and developing reviews.

Typology of Literature Reviews (adapted from Paré et al., 2015).

As shown in Table 9.1 , each review type addresses different kinds of research questions or objectives, which subsequently define and dictate the methods and approaches that need to be used to achieve the overarching goal(s) of the review. For example, in the case of narrative reviews, there is greater flexibility in searching and synthesizing articles ( Green et al., 2006 ). Researchers are often relatively free to use a diversity of approaches to search, identify, and select relevant scientific articles, describe their operational characteristics, present how the individual studies fit together, and formulate conclusions. On the other hand, systematic reviews are characterized by their high level of systematicity, rigour, and use of explicit methods, based on an “a priori” review plan that aims to minimize bias in the analysis and synthesis process (Higgins & Green, 2008). Some reviews are exploratory in nature (e.g., scoping/mapping reviews), whereas others may be conducted to discover patterns (e.g., descriptive reviews) or involve a synthesis approach that may include the critical analysis of prior research ( Paré et al., 2015 ). Hence, in order to select the most appropriate type of review, it is critical to know before embarking on a review project, why the research synthesis is conducted and what type of methods are best aligned with the pursued goals.

9.5. Concluding Remarks

In light of the increased use of evidence-based practice and research generating stronger evidence ( Grady et al., 2011 ; Lyden et al., 2013 ), review articles have become essential tools for summarizing, synthesizing, integrating or critically appraising prior knowledge in the eHealth field. As mentioned earlier, when rigorously conducted review articles represent powerful information sources for eHealth scholars and practitioners looking for state-of-the-art evidence. The typology of literature reviews we used herein will allow eHealth researchers, graduate students and practitioners to gain a better understanding of the similarities and differences between review types.

We must stress that this classification scheme does not privilege any specific type of review as being of higher quality than another ( Paré et al., 2015 ). As explained above, each type of review has its own strengths and limitations. Having said that, we realize that the methodological rigour of any review — be it qualitative, quantitative or mixed — is a critical aspect that should be considered seriously by prospective authors. In the present context, the notion of rigour refers to the reliability and validity of the review process described in section 9.2. For one thing, reliability is related to the reproducibility of the review process and steps, which is facilitated by a comprehensive documentation of the literature search process, extraction, coding and analysis performed in the review. Whether the search is comprehensive or not, whether it involves a methodical approach for data extraction and synthesis or not, it is important that the review documents in an explicit and transparent manner the steps and approach that were used in the process of its development. Next, validity characterizes the degree to which the review process was conducted appropriately. It goes beyond documentation and reflects decisions related to the selection of the sources, the search terms used, the period of time covered, the articles selected in the search, and the application of backward and forward searches ( vom Brocke et al., 2009 ). In short, the rigour of any review article is reflected by the explicitness of its methods (i.e., transparency) and the soundness of the approach used. We refer those interested in the concepts of rigour and quality to the work of Templier and Paré (2015) which offers a detailed set of methodological guidelines for conducting and evaluating various types of review articles.

To conclude, our main objective in this chapter was to demystify the various types of literature reviews that are central to the continuous development of the eHealth field. It is our hope that our descriptive account will serve as a valuable source for those conducting, evaluating or using reviews in this important and growing domain.

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• Published: 13 September 2024

The phenomenon of yoga in the imagination of Turkish nursing students: "The way to place goodness in the heart"

• Özüm Erki̇n 1 ,
• Aynur Çeti̇nkaya 2 &
• Begüm Güler 3  

BMC Nursing volume  23 , Article number:  655 ( 2024 ) Cite this article

Metrics details

The aim of the research is to shed light on the experiences of a group of nursing students enrolled in a yoga elective course who practiced yoga regularly for 14 weeks, regarding yoga and the phenomenon of doing yoga, with a qualitative approach.

This qualitative study was conducted at a public university in Izmir, Turkey. The study sample consisted of 61 students enrolled in the 1st-year yoga course at the Department of Nursing, Faculty of Health Sciences. Except for two students, 59 of them participated in the study. Participants attended a face-to-face yoga course once a week for 1.5 h over a 14-week period. Each session comprised 30 min of theoretical instruction and 60 min of practice. In data collection, an interview form containing five questions was used to understand nursing students' experiences and thoughts about practicing yoga. In addition, A4 sized papers in different colors were presented to the participants. The participants were asked to draw and/or cut a shape by choosing the paper in the color that most evokes yoga. Then they were asked to explain why they chose this color and why they drew this shape. Participants were given one hour. After the data were collected, the pictures drawn by the participants and their descriptions of their drawings were transferred to the computer and included in the analysis. Qualitative data were hand-coded by the researchers. Within in-vivo coding, code names were formed from the participants' expressions. The findings analyzed by content analysis were interpreted with the literature under the themes by presenting quotations.

It was determined that the participants used nature figures (sun, cloud, tree, sky, flower) (f = 75), people doing yoga (f = 12), and sound, light and other figures (bird sound, wave sound, candle, light bulb, traffic light, heart, eye, left key, peace, swing, India, circle, etc.) (f = 29) in the shapes they drew and cut out on A4 sized papers in different colors to describe their experiences and thoughts about practicing yoga. The participants mostly chose blue-green-yellow colors ( n  = 41). With qualitative question analysis, a list of codes was created from the answers given by the students to the questions for the phenomenon of “doing yoga” (number of codes = 98). After the analysis of the data, four categories were reached. The category names and frequency numbers explaining the phenomenon of practicing yoga were distributed as “symbol of health and serenity (f = 345)”, “the way to place goodness in your heart (f = 110)”, “the most effective way to meet the self (f = 93)” and “no guarantee of relaxation (f = 71)”, respectively.

Conclusions

The results indicate that yoga is perceived by nursing students as a multifaceted practice that evokes a range of emotional and physical responses. Most participants associate yoga with symbols of health, serenity, and self-awareness, often using natural elements and blue-green-yellow the colors to represent these feelings. However, there is also recognition that yoga may not guarantee relaxation for everyone, as some students reported difficulties in meditation, physical discomfort, and challenges in focusing. The study highlights the variability in how individuals experience yoga, emphasizing both its positive effects on well-being and the potential challenges in practice. These findings suggest that while yoga is widely valued for its calming and health-promoting benefits, it may not be universally effective in achieving relaxation or mindfulness.

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Introduction

Yoga is a practice that has been subject to many different interpretations and translations over thousands of years. Patanjali's phrase "Yogas Chitta Vrittis Nirodha" translates to "Yoga is the cessation of the fluctuations of the mind" in English [ 1 ]. Hagen & Hagen (2024) have emphasized that yoga is commonly understood in society as a tool for mental calmness and balance[ 2 ]. This provides a comprehensive model for personal development, contributing to the individual's balanced harmony in every aspect—mental, physical, emotional, and spiritual [ 3 , 4 ]. By developing inner awareness as well as meta-awareness, yoga offers a roadmap for individuals to see and understand their own state and surroundings more clearly [ 5 ]. Yoga enhances physical functionality by alleviating pain and discomfort, thereby reducing physical ailments. Moreover, yoga offers physical health benefits, including increased strength and flexibility, as well as improved posture [ 6 , 7 , 8 , 9 , 10 ].

According to Bhavanani (2014), yoga extends beyond mere physical or mental health; it also addresses emotional, social, and spiritual needs [ 11 ]. By increasing personal awareness, it can strengthens both inner attachment and social connections [ 6 , 9 , 12 ]. Research shows that participants' self-confidence increases during yoga practice, and they might gain better skills to manage their mental health. This underscores not only the physical advantages of yoga but also its significant contributions to mental and emotional well-being [ 8 , 9 , 13 , 14 ]. Yoga can fosters heightened bodily awareness, elevates mood, and enhances overall well-being. It also promotes self-acceptance, personal fulfillment, and social harmony. This holistic process provides psychological relief and mental tranquility, aiding in the management of common mental health issues such as anxiety and depression [ 11 ].

Today, young adults increasingly experience stress, pressure, and mental health issues [ 15 ]. Research links young people's stress levels to high demands at school and the pressure to meet these demands [ 16 ]. Additionally, lack of physical activity and sleep problems also can contribute to their difficulties in coping with these issues [ 17 , 18 ]. Academic expectations from parents, especially those from middle-class families, can further increase the pressure on young people, leading them to evaluate their self-worth solely based on their achievements. This adds to the existing academic pressures, causing young people to worry more about future educational and career opportunities [ 19 ].

Yoga can physically contribute to nervous system balance by decreasing stress-related sympathetic activity and stimulating the parasympathetic system. Consequently, it can positively impact stress and mental health issues, particularly in young people. Nursing students, who often undergo a stressful educational period, can also benefit from these effects [ 20 , 21 , 22 , 23 , 24 ]. Therefore, it is recommended to integrate mindfulness programs, including breathing techniques, meditation, and yoga, into the nursing curriculum [ 21 , 22 ]. In the literature, a yoga course was integrated into the nursing curriculum in Turkey for the first time by Erkin and Aykar (2021) [ 20 ]. Most studies with students in the field of yoga in the literature are quantitative, although yoga has been studied in college students using qualitative methods, no studies found in nursing. This is one of the starting points of this research. The aim of the research is to shed light on the experiences of a group of nursing students enrolled in a yoga elective course who practiced yoga regularly for 14 weeks, regarding yoga and the phenomenon of doing yoga, with a qualitative approach. This qualitative study tries to fill this gap in the literature by explaining the imaginary meanings that nursing students attending yoga courses attribute to the yoga experience.

Design and participants

The research, designed in a qualitative type, was conducted during the 2018–2019 academic year. In line with the qualitative research approach, a purposeful sampling method was used. The qualitative method sees the experience of reality as subjective, varying from person to person. Moreover, it is a reliable method for studying a little known or understood area. Therefore, a qualitative descriptive design was adopted to explore students’ knowledge and perspectives [ 25 ].

Participants attended a face-to-face yoga course once a week for 1.5 h over a 14-week period. Each session comprised 30 min of theoretical instruction and 60 min of practice. The content of the yoga course is detailed in Table 1 . The theoretical component included a weekly 30-min PowerPoint presentation covering topics such as the history of yoga, meditation, breathing techniques (pranayama), yoga poses (asanas), chakras, mindfulness, and compassion. The practical sessions were conducted in a tranquil and dimly lit room, following a structured 60-min schedule: 15 min of pranayama (e.g., ocean breath, equal breathing, cooling breath, humming bee breath, alternate nostril breath, kapalbhati pranayama), 30 min of hatha yoga asanas involving gentle stretching and strengthening exercises with each pose held for 5–10 breaths and repeated five times, 5 min of meditation, and 10 min of shavasana. These sessions were led by a yoga instructor (first author) registered with the Yoga Alliance. No home practice was required. According to the course rules, students were allowed up to 20% absenteeism. At the end of the 14-week period, it was determined that students were absent for an average of 1.5 weeks. There was only one change in the planned yoga protocol. Although it was initially planned to use one breathing technique every two weeks, all breathing techniques were combined based on the students’ feedback and used in the sessions after students learned all the techniques (after the 6th week). Class attendance was encouraged through messages in a WhatsApp group. However, attendance was not included in the scoring.

The sample of the research was planned to consist of first-year students enrolled in the elective course "Yoga" in the Nursing Department of the Faculty of Health Sciences at İzmir Democracy University in Izmir ( N  = 61). Two students did not participate in the study because the topic and objectives did not interest them. Data were collected from a total of 59 nursing students on a voluntary basis. After the yoga course, the last week interviews were conducted with 59 participants who voluntarily agreed to participate in the study. Of the participants (n:59), 40 were female and 19 were male, with ages ranging from 18 to 21. Forty-six participants described their health perception as "good," nine as "very good," and four as "poor." (Appendix 1).

Data collection

Data collection was conducted using a structured interview form alongside a creative activity where participants were asked to draw a picture and write a text representing the concept of doing yoga. Data were collected through structured interviews guided by a pre-developed interview Schedule (see Appendix 1). The structured interview form developed for this study included seven open-ended questions and prompts designed to elicit detailed responses from the participants regarding their experiences with the yoga course. Prior to commencing data collection with the main participant group, the interview schedule was pilot tested with five nursing students who met the inclusion criteria but were not part of the final sample. This pilot testing allowed for refinement of the interview questions and ensured clarity and comprehensiveness.

After obtaining the necessary permissions for the research, the students engaged in the yoga course were comprehensively briefed on the study’s objectives, content, methodology, and the individuals responsible for its execution. The last week of "Yoga" course (14th week), students asked to draw a picture and write a text representing the concept of doing yoga. Each student was given colored A4 papers and, for those who wished to use them, colored pencils in the classroom environment. Before starting to draw, students were asked to write their gender on the back of the paper, but not their name or surname. In addition to the picture they drew, they were asked to write their thoughts about yoga and what they drew regarding the concept of doing yoga on a separate piece of paper or in appropriate spaces on their drawing paper. Besides students filled the interview form. They also filled out a structured interview form to capture their experiences and thoughts about practicing yoga. Participants were given one hour to complete the task. After the data were collected, the drawings and their related descriptions made by the participants were digitized and included in the analysis [ 26 ]. For security purposes, the data were stored in Google Drive™ accessible to authors.

To examine subjective experiences, the techniques of "drawing" and "description" were used together, attempting to integrate the strengths of both methods. Participants were provided with A4 papers in different colors and asked to choose the color that most reminded them of yoga. Starting from the theme of "The meaning of doing yoga for them," participants were asked to draw pictures representing their perceptions and to write descriptions related to their drawings. In a similar approach referred to as "projective technique" in the literature, the drawing is accepted as a tool for reflecting emotions. Projection means expression and is based on the assumption that "an individual's behavior is a reflection of their personality" [ 26 , 27 ].

Data analysis and interpretation process

The data were analyzed using an inductive approach. Inductive analysis involves coding the data to categorize it, identifying relationships between these categories, and reaching a holistic picture based on this. The key point in data analysis in this study was to create categorical labels embedded in the data [ 26 , 27 ]. In this study, a code list was developed, data were coded, categories were created, and data were reported within these categories. Data analysis was conducted by the researchers through coding. For some themes, in-vivo coding, which is included in the qualitative research methodology of grounded theory, was used as an inductive coding process. In vivo coding involves creating a theme tag using the code that comes directly from the data, i.e., the participant's own expressions [ 28 ].

All these processes were carried out in collaboration with two field experts (ÖE, AÇ). Similar codes were grouped together to form a certain number of categories and reported to establish the main idea in the data. Comparing codes and categories with the literature aimed to contribute to the validity of the data analysis. At the end of the data collection phase, a conceptual model related to the topic was developed by the researchers [ 26 ]

The research team acknowledges the importance of reflexivity in qualitative research. The first researcher, who has a PhD degree in public health nursing with 16 years of experience in nursing, is an instructor of yoga courses for undergraduate nursing students. The researcher maintained a critical awareness of their own biases and assumptions that could potentially influence the data analysis throughout the research process. We aimed to minimize bias by employing a systematic thematic analysis approach and by regularly discussing the emerging themes with a second author, who is a specialist on qualitative research and has a qualitative PhD thesis in public health nursing. This cooperation contributed to ensuring the findings’ objectivity and reliability. Regretfully, it was not possible to get direct participant input on the findings because of the anonymous nature of the data collection process. The third researcher, who is a master’s degree student in public health nursing with 3 years of clinical experience in nursing, is an instructor of yoga. Nonetheless, we think that the utilization of rich participant quotes in conjunction with the iterative analytic process guarantees that the results truly reflect the participants’ experiences with the yoga course.

Ethics approval and consent to participate

Before starting data collection, information about the research was provided to the school administration, permission was obtained, and contact was made with the participants. Approval was obtained from the Ethics Committee of Manisa Celal Bayar University (02/12/2019, no:20.478.486). Participation was based on voluntariness and willingness, and students were informed about sensitive points related to the teacher-student relationship (such as participation or non-participation in the research not affecting their performance evaluations, etc.). Written informed consent to participate was obtained from all of the participants in this study.

Research validity and reliability

In qualitative research, the researcher investigating the problem is at the center of the research. The main measurement tool in the research is the researcher themselves. Therefore, the issue of objectivity has always been at the center of methodological debates in social sciences. In qualitative research, the concept of "trustworthiness" is considered instead of validity and reliability [ 27 ]. Various criteria of trustworthiness were considered in the processes of this research.

During the data analysis phase, in the creation of the code list, and in the interpretation of the findings, a comprehensive perspective was attempted to be reflected through a thorough literature review on the subject. All records in the data collection and analysis processes were kept systematically. Quotations were made from all data sources. The frequencies of the drawings and descriptions were determined, and those with high frequencies and those that were strikingly related to the topic were included. The data collection and data analysis processes were reported in detail as far as space limitations allowed, and original quotations from the data were included. Furthermore, in the quotations, descriptions written by the participants in their own handwriting were also used.

The number of participants in the study was 56. This number is considered sufficient for an in-depth exploration of the research topic. Students were instructed to create an illustration and compose a text depicting the concept of practicing yoga. Each student received colored A4 paper, and colored pencils were provided for those who wished to use them within the classroom setting. Prior to beginning their drawings, students were asked to indicate their gender on the back of the paper, ensuring that they did not include their name or surname. Alongside their drawings, students were required to write their reflections on yoga and describe what they had drawn related to the practice of yoga, either on a separate sheet of paper or in suitable spaces on their drawing paper. Additionally, students completed an interview form. Participants were allotted one hour to finish the assignment. This approach allowed for a thorough and comprehensive examination of the participants’ perspectives. To enhance transferability, purposive sampling was employed in the study. In purposive sampling, participants are selected to have specific characteristics relevant to the research topic. This approach ensured that the participants’ perspectives would represent the research topic effectively. To ensure dependability, interview questions, data collection, and analysis were consistently applied throughout the entire research process. In this study, to achieve confirmability, all stages of the research were described openly and transparently, aiming to reduce the impact of researcher bias. All transcripts and notes used in the study were stored for reference.

The reporting process of the study adhered to the COREQ (CONsolidated criteria for Reporting Qualitative research) guidelines, as outlined by Tong et al. (2007) [ 29 ]. The study follows CLARIFY 2021 guidelines for reporting yoga research [ 30 ].

Participants expressed their experiences and thoughts about practicing yoga by drawing and cutting shapes on A4-sized papers of different colors. It was determined that they used nature figures (sun, cloud, tree, sky, flower) (f = 75), figures of people practicing yoga (f = 12), and other figures such as sound, light, and others (bird sound, wave sound, candle, light bulb, traffic light, heart, eye, key, peace, swing, India, circle, etc.) (f = 29). Participants mostly chose blue-green-yellow colors ( n  = 41).

A code list was created from the responses of students to questions about the concept of "practicing yoga" through qualitative question analysis (number of codes = 98). After analyzing the data, four categories were reached. The categories describing the concept of practicing yoga were distributed as follows in terms of symbols and frequency numbers: "symbol of health and tranquility (f = 345)", "the way to place goodness in your heart (f = 110)", "the most effective way to meet oneself (f = 93)", and "no guarantee of relaxation (f = 71)" (Fig. 1 ).

Concepts and codes identified in the qualitative analysis of nursing students' perception of the phenomenon of "practicing yoga"

Category 1. Symbol of health and serenity (f = 345)

The subcategories that received the most references from nursing students in explaining the phenomenon of practicing yoga under this category are "Serenity and Peace (f = 169)", "Comfort (f = 120)", "Health, Well-being, Happiness, and Energy (f = 56)". Below is the picture and description of the participant related to the subcategory "Symbol of Health and Serenity" (Fig. 2 ): "The reason for choosing the shape of a cloud and the color blue is that it brings me peace, reminds me to take deep breaths and be grateful. It reminds me that there are beautiful things in life and that I need to enjoy life." Additionally, "when you start doing yoga, your thoughts change, you feel rested, and your heart fills with peace." Participant 7, Female.

Cloud figure (blue) -participant 7

Participant 22 wrote the following in the interpretation of the figure they drew (Fig. 3 ): "The color blue always makes me feel happy and peaceful. I chose this color because yoga makes me feel peaceful and happy. For example, when I feel restless and unhappy, going to the beach, seeing the sea, seeing blue calms me down. Also, when I think of yoga, I imagine an endless deep blue sea. A sea with birds flying over it and a deep blue sky. A painting with sunny weather" Participant 22.

Interpretation by participant 22 (blue)

Participant 35's drawn figure is a butterfly, and their description is as follows (Fig. 4 ): “When I think of yoga, I think of a butterfly. Because when I do yoga, I feel as free and light as a butterfly. I imagine my wings taking me wherever I want inside. The green color relaxes me and makes me happy. The wings of the butterfly in my soul's greenery take me to purity…”.

Butterfly figure (green) -participant 35

Participant 9, in the chosen color and the comment on their drawing, expressed the following regarding the sub-category "Symbol of Health and Serenity" (Fig. 5 ): "I chose this color for its energy. Since energy is important in yoga, I chose orange. I chose this shape because I believe yoga is best done in a natural environment. Yoga reminds me of serenity, the feeling of being in emptiness, and relaxation (Fig. 5 )."

Tree figure and comment (orange) -participant 9

Participant 19, in the chosen figure and the comment on their drawing, stated the following (Fig. 6 ): "Because yoga reminds me of mental and physical health. In my opinion, health is manifested in the combination of blue and green colors. That is, balance in nature is something that exists in the soul and body." Participant 19 depicted a ladder figure in combination with blue and green, defining yoga as "soul and body therapy" (Fig. 6 ).

The place where the moon meets the sun (turquoise)-participant 19

Category 2. The way to place goodness in your heart (f = 110)

The meaning of the phenomenon of doing yoga by participant 11, an 18-year-old female nursing student, was labeled as "being aware of placing goodness in heart" as the category tag. This category, referred to 110 times by the participants, includes the subcategories of "Purification (f = 65)" and "Being a virtuous person (f = 45)". Participants mentioned virtues such as "patience, tolerance, love for all creatures, flexibility, equality, non-prejudice, peace, optimism, freedom" contributing to the concept.

Participant 51, an 18-year-old male who described his health as poor, used the light bulb figure to express "happiness, peace, security" and commented, "It causes positive effects on people" (Fig. 7 ). Participant 51 expressed the following regarding the subcategory " The way to place goodness in your heart" in the figure and comment (Fig. 7 ): "The light bulb illuminating the environment is connected to yoga. Yoga enlightens a person's mind."

Light bulb (yellow) -participant 51

Participant 39, a 19-year-old male, mentioned that practicing yoga leads to "thinking more compassionately." Participant 21, a female, stated, "Yoga is something that requires patience."

Here is the drawn peace figure and comment by participant 46, related to this category (Fig. 8 ). This participant said, "I chose pink because it opens up and gives peace. Of course, there is also light pink, not just dark pinks. I chose this sign because where there is yoga, there is love for all living beings, and where there is love, peace is inevitable."

Peace figure (pink) -participant 46

Category 3. The most effective way to meet yourself (f = 93)

For nursing students, practicing yoga means creating "awareness" and is the most effective way to meet oneself (f = 93). Participant 43, a 19-year-old female with a poor health perception, described feeling "calmer, more aware, and internally peaceful" when practicing yoga, as shown in Fig. 9 . Under the category of "the most effective way to meet oneself," Participant 43's figure and comment about yoga are as follows (Fig. 9 ): "…I chose this color because it gives me peace. The other colors make me restless, but this color makes me feel like I can breathe. Yellow is like an endless void to me. A color that makes me experience everything with all its reality. It's like a sky where you can escape from the chaos of the world and get lost in it…".

The world and heart (yellow) -participant 43

Participant 8 chose a cloud figure, describing yoga as "like rising above the clouds" and wrote the following about yoga practice: "Finding oneself in life, being at peace with oneself… [someone who starts practicing yoga] starts to know themselves, their love for life increases." Participant 8, Female.

Participant 33, a female who chose yellow for its calmness and non-straining quality, described the effect of yoga as "self-discovery" and wrote the following (Fig. 10 ): "You awaken your sleeping mind and body, and find the 'self' within you." Participant 33, Female.

Flower and human (yellow)- participant 33

The statement from participant 48 is as follows (Fig. 11 ): "In this image, what I want to convey is; the individual who practices yoga finds themselves, reaches their essence, and becomes aware of their own existence after a long and perhaps short journey. I chose the color orange because it reminds me that energy exists, is alive, and can be transmitted at any moment. For me, yoga is an indicator of energy. After yoga, the body revives and rejuvenates."

The road (orange)- participant 48

Category 4. No guarantee of relaxation (f = 71)

Among the nursing students ( n  = 59), 16 (27.1%) indicated that they do not recommend yoga. The subcategories of this category include "difficulty in relaxing during meditation/emptying the mind (f = 23)", physical complaints (f = 21)", "difficulty in focusing (f = 18)", and "negative perceptions (f = 9)". Participants used expressions such as "headache, neck pain, back pain, dizziness, exhausting, feeling bad, difficult, fear, nervousness, inability to relax, disbelief" in relation to this category. A 19-year-old male participant, participant 41, stated about yoga, "I cannot meditate, I do not feel comfortable." Participant 44, a 19-year-old female participant who rated her health as poor, stated during yoga, "I cannot fully control my breathing and do meditation, I cannot empty my mind, so I cannot achieve complete peace."

Yoga, often conceptualized in the Western world as a physical practice [ 31 ], is considered a practice that can calm the mind and access a higher state of consciousness where individual and universal consciousness merge, using the body [ 32 ], in yoga traditions, the physical, mental, and spiritual dimensions of the individual are intricately connected [ 1 ]. When we relate the benefits of yoga to traditional yoga theories and systems, it can be interesting to explore its connection with the chakra system and colors. The main focus of yoga can be to regulate the functioning of chakras while awakening the associated energies [ 33 , 34 ]. It was thought that the free association of the students' drawings and descriptions could provide guidance in determining their experiences related to the concept of yoga. In this study, where the experiences of nursing students who took the elective yoga course were evaluated with a qualitative approach, participants mostly chose blue, green, and yellow-colored papers, symbolizing nature. When viewed from the perspective of the chakra-yoga system explained in the yoga course, it was thought that the participants might have resonated with certain energy centers or chakras. Blue, green, and yellow colors are respectively associated with the throat chakra, heart chakra, and solar plexus chakra [ 35 ]. The throat chakra is associated with communication, speech power, intellectual development, creativity, and expression [ 36 ]. Participants 7 and 22, who currently perceive their health as good, and participant 19, who chose blue and turquoise colors, may reflect a desire for in-depth communication and original expression, or a need for improvement in these areas. During yoga practice, especially breathing exercises and poses focusing on the throat region can be worked on this chakra, thus enhancing students' capacity for clearer communication and expressing inner truths [ 37 , 38 ].

The philosophy of yoga emphasizes the importance of harmony and unity with nature, which is why many yoga asanas (poses) are named after elements from nature, such as the tree pose, which symbolizes the stability and balance of a tree through its strong roots and upward-reaching branches [ 39 ]. In this study, visuals related to yoga such as the sun, clouds, trees, sky, and flowers were found. Participant 9 recalling and drawing a tree figure during yoga experiences indicates their awareness of this symbolic relationship. Research has shown that spending time in nature has positive effects on people's mood and mental health [ 40 , 41 ]; similarly, many yoga philosophies emphasize the importance of being in harmony with nature [ 42 ]. Therefore, a student's preference for a natural environment while practicing yoga and associating this practice with a tree in nature is thought to reflect both the healing power of nature and the relationship of yoga poses with elements in nature. This symbiotic relationship reminds us of how interconnected humans are with nature and how yoga practice can strengthen this connection. This aspect of yoga can also encourage individuals to strengthen their relationship with nature and adopt a more respectful attitude towards the environment. This can be seen as a reflection of the principle of 'ahimsa' or non-harming, which is one of the foundational principles of yoga philosophy [ 43 ].

Deep breathing practices are fundamental components of yoga and meditation. Consciously controlling breathing can activate the parasympathetic nervous system and trigger the relaxation response [ 44 , 45 ]. Additionally, breath awareness is part of mindfulness practice and brings the individual into the present moment. Feeling gratitude helps a person recognize the positive aspects of their life and develop a more positive life perspective [ 46 ]. Gratitude practice can improve mental health and allow for greater enjoyment of life [ 47 ]. Participant 7's choice of a cloud shape and blue color is explained by the feeling of tranquility it brings, reminding them to take deep breaths and be thankful, and to remember that there are beautiful things in life that they should enjoy. Participant 7's statement confirms this. The shape of a cloud and the choice of the color blue directing them to take deep breaths, be thankful, remember that there are beautiful things in life, and enjoy life, can contribute to the participant's spirituality [ 48 ]. Such an approach can be balancing both mentally and emotionally, especially for students under academic pressure [ 49 ].

Yoga, meditation, and breathwork (pranayama) practices can be effective in creating a deep sense of peace by bringing individuals to the present moment and calming their inner dialogue [ 50 , 51 ]. Participant 22's statement, " The color blue always makes me feel happy and peaceful. I chose this color because yoga makes me feel peaceful and happy. For example, when I feel restless and unhappy, going to the beach, seeing the sea, and seeing blue calms me down ," also indicates the participant's association of yoga practice with feelings of peace and happiness, demonstrating the potential of yoga experience to provide inner tranquility and balance. Furthermore, the participant's desire to go to the beach and see the sea may refer to the healing and calming effect of nature [ 52 ]. Participant 19 states, " Yoga reminds me of spiritual and physical health. For me, health lives in the colors blue and green, meaning it is something in nature and in the spirit of nature ," and Participant 35 says, " When I think of yoga, I think of a butterfly because when I do yoga, I feel as light as a butterfly. I think my wings take me wherever I want inside me. The color green relaxes me, makes me happy, and the green inside me takes me to purity. " These statements may be associated with the heart chakra represented by the color green. This chakra is considered the center of love, compassion, and connection [ 36 ], and therefore, the association of green with this chakra may symbolize the participant's feelings of relaxation and happiness during yoga practice [ 48 ]. The phrase " the green inside me takes me to purity " in Participant 35's statement indicates that green represents purity and healing in the heart chakra, and the opening of this chakra allows the person to feel more peaceful and purer [ 53 ]. In this context, Participant 35's positive feelings toward green and the sense of relaxation may be a result of balancing and opening the heart chakra, contributing to their emotional experiences such as lightness and tranquility in yoga practices [ 54 ].

Participant 51, despite describing their health as poor, mentioning positive effects such as " Happiness, peace, trust " through the figure of a light bulb during yoga practices, can be explained by the illuminating effect of yoga on the mind. Just as a light bulb illuminates its surroundings, yoga enlightens the individual's mental and spiritual state, capable of transforming negative thoughts and emotions into positive ones. This contributes to achieving a general state of well-being and a positive mood by providing both physical and mental relaxation [ 55 ]. Participant 39 mentioned the effect of " thinking more humanely " while practicing yoga. Participant 21 commented that " yoga requires patience ." Participant 46 chose pink because " It opens up and gives peace within me, where there is yoga, there is love for all living beings, and where there is love, peace is inevitable. " Yoga can facilitates a tranquil mental state, reducing stress and tension, thereby promoting harmonious relationships and fostering peace within individuals and their social interactions. Central to yoga philosophy are humanism and the pursuit of a peaceful life [ 56 ] qualities reflected in participants' experiences, affirming yoga's role in cultivating positive personal and societal outcomes.

In the chakra system, colors and their associated energy centers are believed to promote balance and harmony in our daily lives and physical well-being [ 33 ]. Students' selection of these colors related to chakras may reflect their own energy balances and personal development needs, often unconsciously. Yoga practice can equips individuals with tools to enhance the harmony and integrity of these energy centers [ 57 ]. Participant 43, with a negative perception of health, reported becoming " A calmer person, awareness increases, and inner peace occurs; I chose this color (yellow) because it gives me peace. While other colors make me uneasy, when I look at this color, it feels like it gives me breath, and it continues to an endless void. Yellow, for me, is like escaping from the chaos of the world and getting lost in an endless sky ." Participants finding the color yellow soothing and describing it as providing a sense of freedom and freshness like an endless sky can be associated with the solar plexus chakra, typically represented by the color yellow [ 35 ]. This chakra is linked to self-confidence, willpower, and self-realization. [ 58 ]. Participant 33 described the experince of yoga with a flower and human figure as " Self-discovery ," stating, " you awaken your sleeping mind and body and find the 'self' within ." Participant 8 drawn a cloud figure, describing yoga as " like rising above the clouds," saying, "finding yourself in life, being at peace with yourself… [someone who starts practicing yoga] begins to know themselves, their love for life increases ."These statements and figures reinforce the basic themes of "self-discovery" and "being at peace with oneself" in yoga practice [ 59 ], indicating an important relationship between one's yoga practice, personal growth, and quest for inner peace [ 60 ]. Participant 48 believes that " After a long and perhaps short journey of practicing yoga, individuals find themselves, reach their essence, and become aware of their existence. I chose this color (orange) because it reminds me that energy exists, is alive, and can be transmitted at any moment. For me, yoga is a sign of energy; after yoga, the body revitalizes and refreshes. " The choice of orange suggests a strong relationship between yoga practice and energy, as this color, can be associated with the Sacral chakra, symbolizes vitality, creativity, and emotional balance [ 36 ].

In this study, there seem to be mixed views among some participants regarding yoga practice. While yoga and meditation are generally recommended as tools for reducing stress and enhancing personal well-being [ 24 , 61 , 62 ], some students (participants 41–44) have reported not finding this practice beneficial. For example, some participants have advised against practicing yoga due to physical discomfort (head, neck, and back pain, dizziness), inability to empty the mind during meditation, difficulty in focusing, and negative perceptions. The comments of participants 41 and 44 are thought to indicate their individual experiences regarding their inability to meditate and the discomfort they feel during yoga practice. Yoga and meditation practices can create different experiences in each individual; while they can be relaxing and healing for some, they can be challenging and discomforting for others [ 63 ]. This suggests that yoga and meditation can not universal solutions but practices that should be compatible with an individual's personal preferences, experiences, and health conditions [ 26 ].

Participants' health conditions can influence their experiences during yoga practice. Participants who feel unwell or have a specific health problem may find the practice challenging. This underscores the importance for educators and health professionals to provide stress management and relaxation techniques tailored to individual needs [ 64 ].

Limitations

The qualitative data collected in this study regarding the phenomenon of yoga is in Turkish. However, selecting an international journal for publication and translating the text into English may have limited the full conveyance of the figures and participants' expressions to the readers due to the unique cultural characteristics of the language. The concepts of yoga and chakras, meditation, and similar topics, which were theoretically as well as practically conveyed to the participants during the 14-week course content, may have influenced the participants' views on the phenomenon of yoga. The use of a qualitative design tradition in the research both limited the generalizability of the findings and contributed to the originality of the study.

This study has identified four themes that explain the phenomenon of practicing yoga. These are respectively; "symbol of health and tranquility", "way to place goodness in the heart", "most effective way to meet the self", and "no guarantee of relaxation" themes. The findings will contribute to a more comprehensive understanding of student experiences and ultimately understand their positive and negative experiences. By delving into the student perspective, this research aims to provide valuable insights for educators and healthcare professionals. Most of the research on the phenomenon of practicing yoga is conducted abroad, and it is a less studied area in Turkey. Although yoga, which is becoming increasingly popular in our country, is known to be a practice that makes a person feel good; research on how individuals feel about practicing yoga and how they think about it is specific to the subject. Participants associated practicing yoga with symbols and colors found in nature, emphasizing the importance of its effects on the body, mind, and spirituality. In addition, findings regarding the experiences of individuals practicing yoga, a practice that is also becoming increasingly popular in Turkey, have been obtained. Although it is seen that qualitative approaches such as in-depth interviews and content analysis are used in almost all of the qualitative studies on the subject [ 48 , 65 , 66 ], no study has been found that examines individuals' perceptions by drawing pictures and interpreting them. In this respect, the current research's unique research method can contribute to the literature.

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The authors extend their sincere gratitude to the nursing students who willingly took part in this study. Their participation is greatly valued and appreciated.

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Department of Public Health Nursing, Faculty of Health Sciences, Izmir Democracy University, Izmir, Turkey

Özüm Erki̇n

Department of Public Health Nursing, Faculty of Health Sciences, Manisa Celal Bayar University, Manisa, Turkey

Aynur Çeti̇nkaya

Begüm Güler

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ÖE and AÇ contributed to study design. AÇ contributed to analyze data. ÖE, AÇ and BG write the manuscript. All authors read and approved the final manuscript.

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Correspondence to Begüm Güler .

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Ethical approval for the study was obtained from Manisa Celal Bayar University Non-invasive Clinical Research Ethics Committee (Decision no:20.478.486, Date:02/13/2019). We adhered to the principles of the Declaration of Helsinki and relevant guidelines. Written informed consent was obtained from all participants in this study. Participants were ensured to provide their consent voluntarily and without coercion. Written informed consent to participate was obtained from all of the participants in this study. Before the research, the purpose of the study was explained to the students and that they could leave the study at any time. At the beginning of the study, it was informed that participation in the study was voluntary and that no grade would be given. The evaluation of this course consisted of 10 open-ended questions as part of the year-end assessment. Students were asked to name 10 yoga poses they knew, describe the posture, explain the benefits, indicate the indications and contraindications, and identify the associated chakras. The grade distribution of the students was as follows: AA (n:31), BA (n:16), BB (n:6), CB (n:6).  Necessary precautions were taken to protect the confidentiality of the data, the identity information of the participants was not included in the data collection tools and all personal details in the data collection forms were kept confidential. The identifying images or other personal details of participants are presented in a way that does not compromise anonymity.

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Erki̇n, Ö., Çeti̇nkaya, A. & Güler, B. The phenomenon of yoga in the imagination of Turkish nursing students: "The way to place goodness in the heart". BMC Nurs 23 , 655 (2024). https://doi.org/10.1186/s12912-024-02288-y

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Received : 28 June 2024

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DOI : https://doi.org/10.1186/s12912-024-02288-y

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