Summary of review types

Narrative and systematic reviews vary in their aims. Generally speaking, narrative approaches aim to deepen understanding, whereas systematic approaches have been devised to ensure a rigorous examination of a narrow concept or intervention of interest.

Understanding the aims and uses of both approaches will help you ascertain the quality of the literature reviews you read and can be used to inform your own approach to writing narrative reviews.

Narrative reviews (sometimes referred to as traditional reviews)

Narrative reviews provide an overview of the topic of interest, interpretations, and critique. They typically provide the development of a concept or argument over time, define key terminology, justify the chosen theoretical stance for the work being positioned and frame the objectives, and any research questions (if they’re needed).

Whilst academic rigour is important, there are no standardised protocols for narrative approaches. This provides authors with the flexibility to explore broad concepts, position developing ideas, or establish new frameworks.  Common criticisms of narrative literature reviews include authors showcasing work that suits their narrative and lack of critique of methods and quality of the word cited.

Types of systematic reviews

Scoping reviews

Scoping reviews provide a snapshot of what evidence is available about a particular topic, concept, or issue within specified parameters.  For example, an author may wish to find out what research exists about the efficacy of a specific sleep intervention and specify the research included must be peer reviewed, published in research journals, and have been published between specific dates.

The available research is summarised on tables and similarities and contradictions are discussed. Scoping reviews map the evidence available literature but do not necessarily critique studies or report on potential bias. They are generally used to inform future systematic reviews or research.

Those writing scoping reviews are strongly advised to follow a recognised protocol, such as PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses – Scoping review extension). Visit PRISMA Statement’s website for additional guidance

Systematic literature reviews

Visit the British Medical Journal’s guidance and exemplars for reporting systematic reviews which sets out the approach taken to PRISMA systematic reviews.

It provides helpful guidelines for writing each section of a systematic review paper which you may find helpful when writing some sections of your narrative reviews.

Meta-analyses

Researchers and authors interested in a particular area that has already been subject to previous research, sometime carry out a meta-analysis. The process involves systematically searching for pre-existing research and then analysing all the results to determine what the overall outcomes are from the collective studies. In order to do this effectively, it’s essential that the studies are of high quality and that the measures used across studies are comparable. When doing your own literature reviews it is helpful to check to see whether any meta-analyses of the topic you’re searching have already been subject to a meta-analysis. Those which adhere to a pre-determined approach (such as PRISMA or Cochrane) are generally considered to be more robust than those which follow no guidelines.

View the PRISMA checklist for meta-analyses, published on the PRISMA Statement website

The Cochrane approach is commonly used in medical studies.