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NC3Rs: National Centre for the Replacement Refinement & Reduction of Animals in Research
Guidance | Tool

Introduction to systematic reviews

What is a systematic review?

A systematic review is a powerful method used to assess accumulating evidence related to a specific research question. It uses a systematic and structured approach, with a rigorous search of the published literature, to identify and appraise the results of existing studies. A meta-analysis can follow a systematic review, where results from individual studies are pooled and statistical methods are used to summarise the results. In clinical research, systematic reviews are considered to provide the most robust evidence in evaluating effectiveness of interventions.

Why do a systematic review of animal research?

There are a number of potential 3Rs benefits that can be achieved with a systematic review:

  • They can help you choose the most appropriate animal model for your study.
  • They can inform robust sample size calculations, which can reduce the number of animals used in future studies
  • They can help to determine whether shorter, single, low severity procedures and tests are as predictive as longer, multiple, or more severe alternatives

Systematic reviews can also identify areas of weakness in experimental design and highlight their impact on study outcomes. This can often be the first step in raising standards in a particular research area.

In industry as well as academia, evidence-based decisions and translation of preclinical research can be facilitated by systematic review.

What is SyRF?

SyRF is a free-to-use online platform for researchers to perform systematic review and meta-analysis of animal studies.

SyRF was developed by the CAMARADES group using an NC3Rs infrastructure award and was launched at an NC3Rs event in London in March 2017 with expert speakers and 80 attendees from the scientific community.

the logo of the CAMARADES group at the University of Edinburgh

How to do a systematic review of animal research

The educational resource on the SyRF website will take you through the process of performing a systematic review, step-by-step, from how to define your research question, through to practical instruction on how to screen for and annotate research papers, and finally how to interpret and prepare your results for publication.

The SyRF app has in-built tools that substantially reduce the workload of systematic review and meta-analysis, including:

  • A search tool that automatically updates your review when new papers are published
  • Machine learning that assists screening of research papers
  • Automatic annotation to help you identify key quality criteria
  • A meta-analysis app with statistical tools to analyse your data
  • Dedicated support from experts in systematic review via the SyRF helpdesk.
A flow chart showing the stages of a systematic review, from beginning to end

Use the download link below for slides providing an overview of performing a systematic review using SyRF.