This guide is primarily aimed at staff and post-graduate research students undertaking a systematic review or evidence synthesis. Whilst the focus is primarily health sciences, the guide will be relevant to staff and students from other disciplines too.
Before working through the steps involved let's first outline what a systematic review is.
A systematic review is a research method used to summarise and synthesise all available evidence relating to a well formulated research question. It is conducted in a systematic and transparent way. A systematic review is therefore a form of ‘evidence synthesis’.
Evidence synthesis methods are evolving. Evidence synthesis refers to any method of identifying, selecting, and combining results from multiple studies.
Why are systematic reviews important?
A scoping review is a type of research synthesis that aims to map the key concepts, types of evidence, and gaps in the literature on a particular topic. Unlike systematic reviews, which typically focus on answering specific research questions by synthesising the results of relevant studies, scoping reviews are broader in scope and are used to explore or map the extent and nature of research or evidence on a particular topic. Scoping reviews are sometimes conducted in advance of undertaking a full systematic review.
Read more about scoping reviews in: What are scoping reviews? Providing a formal definition of scoping reviews as a type of evidence synthesis. JBI Evidence Synthesis 20(4):p 950-952, April 2022.
A narrative review is a type of literature review that provides a comprehensive summary of the existing literature on a particular topic. Unlike systematic reviews, narrative reviews do not follow a strict methodological approach and are often more flexible and subjective.
A rapid review is a type of evidence synthesis that aims to provide timely and relevant information to decision-makers by streamlining and accelerating the traditional systematic review process. Rapid reviews maintain systematic review principles but use abbreviated methods to speed up the review process.
A meta-analysis is a statistical technique used to combine the results of multiple studies that address a common research question. By pooling data from several studies, a meta-analysis aims to derive a more precise estimate of the effect size or the relationship between variables than any single study could provide on its own. A meta-analysis is often conducted alongside a systematic review.
An umbrella review, also known as a review of reviews, is a type of evidence synthesis that compiles information from multiple systematic reviews and meta-analyses on a particular topic. It provides a high-level summary of the evidence by consolidating findings from various reviews.
Unlike traditional systematic reviews, a mixed methods systematic review (MMSR), combines qualitative and quantitative evidence to comprehensively address a research question.
While there is a degree of complexity in conducting MMSR, the core intention is to combine quantitative and qualitative data (from primary studies) or integrate quantitative evidence and qualitative evidence to create a breadth and depth of understanding that can confirm or dispute evidence and ultimately answer the review question/s posed" (JBI Manual for Evidence Synthesis, 2024 - Introduction to mixed methods systematic reviews)