Health and Social Care

Literature reviews are a form of evidence synthesis, which is how research and other sources are analysed, evaluated, and brought together in order to form bodies of literature. This strengthens the evidence to then allow it to be used to implement changes though an evidence-based practice approach. In order to implement evidence in practice we need to be confident of its reliability and accuracy, which healthcare reviews address through the appraisal and synthesis of multiple sources of evidence. We cannot rely on a single source of evidence to implement changes, we need a large body of evidence to be confident to apply it. 

The hierarchy of evidence below demonstrates how literature reviews and other forms of evidence synthesis, such as guidelines, appear at the top of the hierarchy. Secondary sources that analyse and synthesise literature are stronger than individual studies or other sources.

In health and social care there are a number of different types of review. The resources below give an outline of the different types and outline the differences between them:

Grant, M. J., & Booth, A. (2009). A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information and Libraries Journal, 26(2), 91–108. https://doi.org/10.1111/j.1471-1842.2009.00848.x 

Sutton, A., Clowes, M., Preston, L., & Booth, A. (2019). Meeting the review family: exploring review types and associated information retrieval requirements. Health Information and Libraries Journal, 36(3), 202–222. https://doi.org/10.1111/hir.12276  

If you are doing a literature review as part of an academic assignment then please ensure you follow the requirements and any methods set out in your assignment brief. You may be advised to do a specific type of review, but when reading the guidance of how to conduct one find that it differs from your assignment brief. If so, discuss this with your supervisor or module leader.

Choosing a Review Type

You need to understand the purpose of different review types and match this up with what you are intending to achieve from carrying out your review in order to select the most appropriate type. You can include this explanation and justification within your write up. As well as the guidance above please see some further resources below to support your decision making.

Munn, Z., Peters, M. D. J., 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), 143–143. https://doi.org/10.1186/s12874-018-0611-x

Jonkoping University. (n.d.). Which review is right for you? https://guides.library.ju.se/c.php?g=690269&p=4943634

Right Review. (2024). Right Review Tool. https://rightreview.knowledgetranslation.net/

There are a number of published reporting and conducting guidelines and handbooks to support you in both carrying out and writing up your review. These help to ensure the quality and transparency of your review by ensuring you have included and conducted your review in a way that meets established methodological expectations.

Reporting guidelines give information on what you need to include in the write up of the review. Conducting guidelines provide more methodological guidance on how to carry out and undertake each stage of a review, not just stating what you need to include/report. When using these they need to be cited and referenced and the wording you would use needs to distinguish if it is a reporting or conducting resource, and therefore how it has been used. Examples:

'this review/protocol was reported using . . . '

'the conducting of this review was guided by . . . '

A lot of these were designed for quantitative systematic reviews of interventions, however a number of resources now exist for different types of evidence synthesis reviews. Below are resources of some of the most commonly used guidelines.

PRISMA

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement consists of a 27-item checklist that covers the elements needed in the write up of a systematic review, and a flow diagram.

There is an article giving further explanation of every element of the checklist and a glossary of terms.

PRISMA also have guidance for reporting protocols, known as the  PRISMA-P extension.

There is also a checklist extension for Scoping Reviews called PRISMA-ScR, which is very similar to the Systematic Review checklist but with some key differences.

Also a more in-depth explanatory paper for this checklist as well.
 

Cochrane

The Cochrane Handbook for Systematic Reviews of Interventions needs to be followed if you were to publish a review or review protocol in the Cochrane Library of Systematic Reviews.

There are a set a reporting guidelines for both review protocols and full reviews.

Key aspects of the Cochrane handbook are collated as the Methodological Expectations for Cochrane Intervention Reviews – takes you through steps needed to conduct.

The Cochrane Handbook Chapter V also details methodology for conducting Overviews of Reviews.

The Cochrane Qualitative and Implementation Methods Group have published a series of 6 papers covering qualitative evidence synthesis methods.

The Cochrane Rapid Reviews Methods Group and Cochrane Qualitative and Implementation Methods Group (CQIMG) have published a recent article on guidance for rapid qualitative evidence synthesis.

Other Guides

The JBI Manual for Evidence Synthesis separates SRs out by types of evidence included, as well as having chapters on Mixed Methods Reviews, Scoping Reviews and Umbrella Reviews.

RAMSES reporting can be used for realist reviews and meta-narrative reviews.

The ENTREQ checklist can be used to report reviews of qualitative literature, alongside a fuller article explaining the development of the checklist.

Further reporting and conducting guidelines can be found on this useful page from the University of Illinois.

Booth, A. (2016). EVIDENT Guidance for reviewing the evidence: a compendium of methodological literature and websites. https://www.researchgate.net/publication/292991575_EVIDENT_Guidance_for_Reviewing_the_Evidence_a_compendium_of_methodological_literature_and_websites

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