Thing 20: Systematic Reviews
Writing a systematic review can seem daunting, and trying to figure out what research has been done on a particular topic can leave you scratching your head. To help get you started, Patrick Condron revisits his 2017 Thing post to walk you through the systematic review landscape.
Systematic reviews are the gold standard for answering a question that is informed by a base of evidence. The process is designed to explore the literature thoroughly and to make an unbiased decision based on research that meets your pre-set inclusion criteria.
Start your systematic review by developing an appropriate research question. It should not be too broad (expect 10-50 papers to be included on the topic), and specific enough to interest other researchers and decision makers in the field. Before starting, read other systematic reviews in your discipline to get a feel for the process involved, and to check if your question has already been answered.
Most systematic reviews will query between three and eight databases with a replicable search strategy. Use subject headings and search operators to reduce irrelevant material returned by your search. Taking time in search design will save you time when screening results. Librarians can assist with making the best use of each database, while systematic review tools or reference management software applications are useful for managing and de-duplicating the results. Next up, scan the titles and abstracts of your results, to find papers of interest. You have to define strict inclusion and exclusion criteria for your review; once you have gathered relevant papers, assess them against these criteria to determine which papers should be included in your review.
With the papers selected, develop a table of data items to collect about each paper and extract this information. In order to reduce bias, you need two reviewers to extract the study data from each paper. Also assess the quality of the methodology applied in the study. Finally, you may be able to undertake a meta-analysis with similar findings or describe the findings covering key themes and key objectives to answer your research question. Many journals now publish completed systematic reviews. Your research plan or protocol can also be published.
You can find more detailed information on the steps involved in the systematic review process in our Systematic Reviews library guide.
That Thing you do: integration into practice
University of Melbourne researchers have published many systematic reviews, so there is likely to be someone in your department who can share their experience and expertise with you. Search the term ‘systematic review’ in Find An Expert to see the many researchers and publications produced. Also have a look at the databases and tools below.
Review protocol registries
Check to see if someone else is working on your question, and register your intention to undertake a review at one of these international registries:
- PROSPERO (International prospective register of systematic reviews)
- Open Science Framework
- Research Registry
Systematic review databases
Try browsing the Cochrane Library by topic, or search for your topic on the Campbell Collaboration website. These organisations are the pinnacle for systematic review production in the health and social sciences.
Covidence is a web-based tool for systematic review management. It is designed to support review teams perform double-blind reviews and screening of items for inclusion. In 2015, Covidence was selected by Cochrane to become the standard production platform for Cochrane Reviews. The University Library has a Covidence institutional subscription which pays for your review work area. The Systematic Reviews library guide includes instructions on accessing Covidence and joining the University Library account to your personal account.
Systematic reviews are undertaken within a methodological framework. For quantitative research reviews, the most common framework is PRISMA (Preferred Reporting Instrument for Systematic reviews and Meta Analyses). This has 27 checklist items that may need to be reported in a quantitative systematic review. Each item is explained in a document called PRISMA Explanation and Elaboration (PRISMA E&E). Following the checklist not only makes the systematic review more likely to be published, it also improves the reading quality of your manuscript.
Another commonly-undertaken type of review is the Scoping Review, which examines themes within the literature in relation to a problem or issue. The Joanna Briggs Institute has a detailed framework for researchers considering the scoping review format.
- The Systematic Reviews library guide contains more information on the process and services available for researchers thinking of undertaking a review.
- Cochrane Interactive Learning has self-paced online modules that guide you through the entire process of authoring a systematic review with Cochrane, which can be used to understand the process for any systematic review.
- McCool R, Glanville J. What is a systematic review? Hayward Medical Communications, 2014. (Resource access only available to University of Melbourne staff and students, login required)
- Our librarians can point you in the right direction with a research consultation.
About the author
Patrick Condron is responsible for liaison to research staff and graduate research students in the Melbourne Medical School and Melbourne Dental School. He provides assistance with systematic reviews undertaken in the schools, and provides expert advice on advanced searching techniques to librarians and academic staff across the University.
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