The PRISMA - Preferred Reporting Items of Systematic reviews and Meta-Analyses statement from 2009 has recently been updated (March 2021) and is an evidence-based guideline with a minimum set of items for reporting in systematic reviews and meta-analyses. It was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. A dedicated global team of methodologists, search specialists, biostatisticians and systematic reviewers have spent the last few years diligently updating the PRISMA statement, including Head of Cochrane Denmark and CEBMO, Asbjørn Hjórbjartsson.
While this may sound simple, it is anything but. Systematic reviews are complex, using an array of methods from the identification of studies through to the synthesis of results, and careful reporting is required so that users of the review (such as guideline developers, policymakers, healthcare providers and patients) are able to understand what was done and how the findings might apply to them.
The updated open-access PRISMA statement is available online and published in no less than five leading journals - including BMJ, PLOS Medicine, Journal of Clinical Epidemiology, Systematic Reviews and International Journal of Surgery. It represents a major global collaborative effort that was sustained throughout the many challenging months dominated by COVID-19 throughout 2020. The updating process involved lengthy consultation and a comprehensive survey of systematic reviewers, journal editors and methodologists with experience with and interest in the use of the previous iterations of PRISMA. It contains both an update to the PRISMA flowchart, as well as new preferred items to report. You can read all about this in the BMJ article.
If you want to explore the process behind the update of the PRISMA statement from 2009 and the creation of the 2020 version, you can explore the development in an article in the Journal of Clinical Epidemiology here.
Photo: PRISMA workshop participants, Cochrane Colloquium, Edinburgh 2018
Article published: 05.05.2021