Skip to Main Content

Health and Social Care

Library subject guide for nursing, midwifery, AHPs, health and social care

Literature reviewing - the overview

A stack of open booksA literature review can form a part of any assignment but it is perhaps more commonly associated with work at dissertation and Masters levels. It should represent an overview of a specific question , sketching out the state of that subject and the ongoing debates and research at that point in time. Your literature search will have been wide ranging and systematic in approach and may use sources as wide ranging as books, journal articles, government policies, web pages, theses etc. Your review of the literature will involve critical analysis of the arguments and positions, not just a description of the literature.

Look at the powerpoint slides below for a brief outline of literature reviewing.

 

In health and  social care the two main types of literature review are the narrative or integrative literature review and the systematic review.

Traditional or Narrative Literature Review

  • Broad in focus. Does not always address a specific question.

  • Not comprehensive in literature included.

  • Does not  always state reasons for inclusion of papers.

  • Not structured in approach to searching for literature or critical appraisal

   Example of a traditional /narrative literature review

A narrative review is often the approach taken at Masters dissertation level and can still be rigorous and based in systematic approaches. The following article provides a good overview of these within healthcare.

Sukhera, J. (2022). Narrative Reviews: Flexible, Rigorous, and Practical. Journal of Graduate Medical Education14(4), 414–417. https://doi.org/10.4300/JGME-D-22-00480.1 


Integrative Review

  • Reviews, critiques, and synthesises  literature on a topic in an integrated way.
  • Summarises past theoretical and empirical literature on a topic.
  • Attempts to generate new frameworks and perspectives on that topic.
  • Does not always use explicit systematic approaches in searching or data analysis therefore quicker to complete  (when compared with systematic reviews).
  • Potential for bias and lack of rigour.

Example of an integrative review


Systematic Review

A review of research literature using  a systematic, explicit,  accountable and dcocumented methodology.

The key characteristics of a systematic review are:

  • Rigor: use of systematic methods to answer set research question

  • Transparency: every step is described; nothing left to reader’s imagination

  • Replicability: a second researcher should arrive at the same conclusions

 

Systematic reviews are carried out by a team, or at least two, individuals and usually take 12 months or more to undertake.

Students undertaking undergraduate, Masters or PhD dissertations should take a systematic approach to reviewing the literature but they will not be expected to complete a full systematic review following full Cochrane Library methodologies.

 

Example of a systematic review

 

 

 

A good literature review should:

  • Address a focused, explicit research question.
  • Take a systematic approach to the searching of the literature.
  • Document the search process so that it is replicable  by others  (often a requirement for publication within many academic journals)
  • Demonstrate that a wide range of sources have been searched.
  • Undertake a critical analysis of the retrieved literature, not merely describe what has been read.
  • Justify why particular items of literature are being referred to. They should summarise the current state of research,  perhaps debates that have taken place over a period of time within that topic or arguments for and against a particular aspect of the topic.
  • Relate the question to the larger body of knowledge within which your topic sits, and to put your work into context.
  • Summarise the current state of the research evidence.
  • Identify the gap in the literature that your research question is going to answer.

 

Common Mistakes

  • Review is too descriptive. No critiquing or critical evaluation of the evidence. No identification of strengths and weaknesses. It becomes an essay, not a review. It does not set the foundation for your own research process.
  • It becomes a dumping ground to write down everything you know about the topic  or is presented as a series of quotes from the papers you have read.
  • Not enough time has been allocated to searching and reviewing the literature. Do your literature reviewing early. It helps inform your final research question, future methodologies and identifies whether there is indeed a "gap" in the current research literature that your queston is going to answer.
  • Literature used is not from scholarly peer reviewed sources.
  • There is no documentation or explanation of how the search was undertaken and the key terms used. No explanation of inclusion/exclusion criteria.
  • Referencing does not follow the School guidelines. It is not consistent in style or presentation.
  • There has been no revision or proof reading. Thinking develops as you write. Go back over what you have written a few days after you have done it. Check grammar and language – give it to someone else to proof read.

Here are 5 top tips towards a stress free  literature review

Literature reviewing - the process

Formulating a review question is a key stage of the review process as this impacts the development of the outcomes of the review, the eligibility criteria for selection, and the development of the search strategy. If you make changes to your review question after already moving on to other stages of the review you may need to go back and make changes to these other steps.

Ideally a review should add new knowledge to that topic or field, so you want to develop a question that has a new focus or outcomes that has not previously been explored. Sometimes it is appropriate to update a previous review using the same question and outcomes to see if the findings of the review have changed with the inclusion of new literature since the previous one was published.

If you are a Masters student it is particularly important that you choose a topic that is both viable and manageable within the word count and timescales for completion. Viable means a topic where there is published literature, you cannot do a literature review on a question where there is no available literature. Manageable means selecting a focused topic where there will not be too vast an amount of literature to include as you have a word count limit and a timescale in which to submit the assignment.

To help you develop a question try and identify an area from practice that you are interested in – ideally something the practice area can benefit from which will give value to your review findings.

The question you develop from this topic should be focused, manageable and answerable within the timescales you have.

Scoping the Literature

This is where we run initial literature searches around our topic of interest to get an initial idea of what literature is out there. This will help us to:

  • Check what reviews have already been done on this topic.
  • Check our topic is viable - there is enough literature out there.
  • Check our topic is not too broad - too much literature out there.

From these initial searches of the literature you can start to refine your review question, broadening or focusing as necessary. Please see the following video on Scoping Searches to Refine Your Topic for an example of how this works in practice.

Question Formulation Frameworks

Question formulation frameworks are used particularly within healthcare to help you identify the key concepts of your topic, to then structure into a research or review question. The following document shows you examples of the most commonly used ones in healthcare, breaking down each framework into what the concepts mean, giving examples in practice of questions structured using that framework, and suggestions of review outcomes and types best suited to each framework.

The eligibility criteria can also be referred to as the inclusion and exclusion criteria. This is a set of criteria you will develop which you will use during the selection process of the review to decide which sources of literature to include and exclude. This criteria helps to reduce selection bias, because every decision you make should be based on this pre-determined set of criteria. 

When take a systematic approach to searching and selecting the literature your eligibility criteria needs to be very detailed, both for you to be able to make decisions for each of the pieces of literature you have found, but also for someone else to be able to use the criteria with the same set of literature and make the same decisions as you. If you are doing a review as part of a review team for publication then there should be a minimum of two people involved in the selection of the literature, both using the same criteria to make selection decisions. This aligns to the systematic criteria of transparency

When developing your eligibility criteria think about the following elements:

  • Each of your question concepts from your question formulation framework and detail exactly what criteria would mean a source would be included or excluded in relation to each question concept.

E.g. your population group is people with dementia, so as inclusion criteria you would state that each literature source needs this population group and any source without this population group would be excluded. But what about literature where participants and both people with dementia and people with Parkinsons. Would this be included or excluded? Your criteria needs to be detailed enough to capture all of the potential decisions you would need to make.

  • The study criteria for research literature, so the methodology, design and any further details. Depending on your review question there will sometimes be specific types of data most suited to answer the question, so sometimes either quantitative or qualitative data only would be appropriate, and sometimes only specific study designs like randomised controlled trials

E.g. you're question is exploring the experiences and views of a particular group of participants, therefore the data most appropriate to 'answer' this question would be qualitative.

  • Types of publications, so are you only including primary research or wider sources of literature? Even with primary research there are a number of different source types this could be presented in such as journal articles, theses, conference proceedings.
  • Publication dates, so is there a specific date range you will only be including literature from? Try to think about the context of your specific topic/question and what would make something too old. 

E.g. there has been a new guideline in your topic area published in a specific year with major changes to how a specific procedure is done in practice, meaning that older literature is not relevant to the current guideline. Topics related to technology could be outdated more easily due to specific technological developments in a specific field or equipment. 

A search strategy includes where and how you are searching. Can someone else use your process to find what you found? This aligns with the systematic criteria of being transparent.

You need to plan and include the following detail in your write up to allow someone else to replicate your search:

•Specific databases, journals, websites etc.
•Any other search methods e.g. citation tracking.
•The search terms you are using.
•The search fields you are searching in.
•How you are inputting the search terms and how Boolean (AND, OR) is being used.
•Methods other than the search terms e.g. phrase searching, truncation, wildcards, proximity searching.
•Limiters you are using to refine search results.
Please see the following video on Planning Search Strategies as well as the document below which is a template to help you plan your searches.

When searching in databases most of the time you want to use the advanced search feature to build a search that will find a more relevant set of search results. To do this you need to be able to plan effective search strategies, using appropriate keyword search terms, and inputting these into the database in the most effective combination.

The videos below demonstrate how to input a planned systematic search strategy into a database. Different database platforms will look slightly different, but the principles for doing an advanced search are the same across them all, but differences are demonstrated.

Searching in EBSCO databases (CINAHL, Medline, APA PsycInfo etc.)

Searching in PubMed

Searching in Ovid

Searching in Web of Science

Searching in Proquest

The selection process is where you will use your eligibility criteria to select the literature for inclusion in your review. Considerations needed are:

How are you going to select included studies from your set of search results?
Who will be involved in this?
How are you going to agree on methods if more than one reviewer is involved?
What eligibility criteria are you going to use?
How are you going to record and document this decision-making process?
 
The PRISMA Flow Diagram can be used to document the search selection process. Use the second document down in the list – for new reviews and includes options for non-database searching to be included. If you are using the PRISMA or Cochrane reporting guidelines they explicitly require this process to be documented – use this template that already exists! Please see this Useful article on common questions on using the new flow diagram and tracking records. 
Please see the Selection Process Using PRISMA video I have created taking you through each stage of the diagram.
 

Keeping track of literature

Writing a literature review will mean that you will collect a large number of pieces of information from many sources.  Before you begin searching, give some thought as to how you are going to manage this information. 

How will you keep track of how you do this?
Where are you going to store the studies throughout the process?

Reference management software will enable you to automatically  export references you collect from database searches and store them in the reference manager.   Once you have read each paper you can then make personal research notes and store these within each reference inside the reference manager.

Use the software  to format the citations within the text of your review. It will also produce the reference list at the end of your document formatted in a style of your choosing e.g.  APA 7th.

See  our Reference Management LibGuide on how to get started with Endnote or Mendeley, Edinburgh Napier’s referencing management software.

NHS Scotland users can also use the Refworks ref management software supplied on the NHS Knowledge network site instead of Endnote,  if they would prefer.

What is critical appraisal? 

Critical appraisal/quality assessment is a specific aspect of critical analysis where you examine and assess research in order to judge its:

•Validity
•Trustworthiness
•Value and Relevance
 

You are evaluating the quality of the research and how it has been conducted, as well as the findings themselves and how it has been reported. Please see the following video by Cochrane on an Introduction to Critical Appraisal for a more in depth description.

 

Why do we do it?

•Allows you to identify any issues which could impact the reliability of the findings.
•If you are using the source as evidence in an academic assignment you want to be sure you are using reliable sources to back up your arguments.
•If you are doing a literature review this could impact your overall review findings if not addressed – review conclusions are stronger if studies with a low risk of bias are used.
•It could impact how confident you would be to apply the findings into practice – a vital part of evidence-based practice in healthcare.
 
How do we do it?
 
Understanding the research methodologies and designs of the included literature is a vital part of being able to critically appraise the literature. You need to know how that study design should be conducted and what a 'good' version looks like, as well as being to identify potential weaknesses and bias. 
The SAGE Research Methods database includes a large number of resources to help you understand research methods and designs in more detail. Please see the following video of Using the SAGE Research Methods Database which demonstrates how to use it effectively.
 

Critical appraisal is often carried out using checklists that help signpost areas to look for while reading a paper. There are different types of checklist depending on the type of research you are reviewing.

The following document lists some of the main appraisal tools used in published reviews and would be a good place to start when deciding on which tool to use. 

Further Critical Appraisal Resources

Book

Book How to read a paper Greehalgh, T (2019) How to read a paper :  the basics of evidence-based medicine. 6th ed. Wiley Blackwell

 

Videos

Two excellent videos from Andrew Booth at SCHARR at the University of Sheffield. These take you through the actual process of appraising papers using the CASP tool.

Appraising a Quantitative Study             [13 mins]

Critical Appraisal of a Qualitative Study  [12 mins]

Data Extraction and Charting

Your literature findings need to be presented and discussed both descriptively and analytically. It is usually to present a summary of the included sources in the form of a data extraction or study characteristics table, a process also referred to as data extraction and charting your results.  The video below covers how to present your findings in this way.

Analysing and Synthesising the Findings of the Literature

Depending on the type of review you are doing and also whether the review is being done as an assignment, there may be differing expectations of how you analyse the included literature sources.

At Masters dissertation level you would be expected as a minimum to provide a narrative thematic analysis, where you compare and contrast the literature to identify patterns and themes and interpret these in relation to your review question. You can use a deductive approach where you start with a pre-existing framework of themes, or an inductive approach where themes are generated from reading the literature.

At PhD or researcher for publication level there would be an expectation of a more complex analysis of the literature, appropriate to the literature sources. A scoping review including a wide range of source types would likely best be suited to a narrative analysis, but if the review literature is all research then an appropriate quantitative, qualitative, or mixed methods form of analysis of the data would be expected.

Most Systematic Review conduction and reporting guidelines are designed around an analysis of quantitative data, so if this does not fit the data of your literature you may need to use different analysis and synthesis guidance. There are a number of different analysis methods, some examples and resources are listed below as a starting point but you may also want to look at examples of similar reviews fur further methods.

  • Chapters 10 and 11 of the Cochrane Handbook covers quantitative meta-analysis.
  • Chapter 12 covers over methods, however these are all still mainly quantitative methods.
  • The eMergE reporting guidance covers meta-ethnography qualitative synthesis, and the ENTREQ statement can also be used for qualitative synthesis.

Recommended Reading