Systematic reviews: A guide for radiographers and other health care professionals

This paper offers guidance on performing systematic reviews to help up-skill radiographers and other health care professionals. It considers why systematic review is critically important to Radiography. Using a relevant example i.e. to investigate adverse effects related to MRI contrast agents it then examines the features of a systematic review and explains how diagnostic research evidence within a systematic review is evaluated. The paper then discusses the threats to validity of systematic reviews on a step by step basis. Five key steps are considered: Step 1: define the purpose of the review via a well-structured question. Step 2: determine the parameters (eligibility criteria) for a comprehensive systematic literature review that will address the research question. It is the wide range of material reviewed in this way that makes the work a systematic review, rather than an analysis of papers you happen to have. Step 3: Assess the quality of the literature you have found. Generally peer-reviewed papers published on a database such as Medline, which in the example given was established as an eligibility criterion, are considered to be high quality, but the actual impact factor/SCOPUS score of each journal is variable and should be considered. Step 4: Synthesise what the literature has revealed; appropriately extract data and summarise it; identifying any study differences. This requires the use of suitable methods for agreeing and summarising the results. This may involve a meta-analysis to collate the results from several studies. Step 5: interpret the findings to draw inferences from the resulting review and from the results of a meta-analysis if undertaken. This paper then provides a check list for guidance of those involved in writing systematic reviews and finally summarises the paper. A glossary of terms appears at the end of this paper.