16 Feb, 12 | by BMJ Group
Systematic reviews have something of an image problem. To the uninitiated, they can be considered too effete because they run on for hundreds of pages, with lots of forest plots and risk of bias calculations. And what is a GRADE table? I know that I generally head straight for the conclusion section of the abstract—does it work? How much do I take? Of course, I have drunk the Kool Aid and come clean about my status as a Cochrane reviewer yet I am always aware of the reaction of one of my senior and greatly esteemed colleagues who upon hearing of me bringing in a grant to develop a centre for systematic review at the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B) cornered me and demanded, “Is this how you use your powers? For bad!”
However, in an effort to make the reporting of systematic reviews more useful to decision makers, I recently participated in a consensus meeting on creating a equity-extension of the preferred reporting items for systematic reviews and meta-analyses (PRISMA) in Bellagio. The original PRISMA checklist was developed to improve the quality of reporting for systematic reviews of health, particularly those that capture clinical benefits and harms. PRISMA consists of a 27 item checklist that guides the development of the report from a systematic review to the title, the discussion, the tables, and everything in between.
The meeting continued over five years of work led by the Cochrane & Campbell equity methods group. Our hosts were Peter Tugwell, Mark Petticrew, and Vivian Welch with the location made possible by the Rockefeller Foundation. The 20 participants came from around the globe with diverse experience of working with systematic reviews either as reviewer authors, review group leaders, journal editors, or as programme coordinators with an eye on equity-related issues for organisations like WHO and PAHO.
There was no bickering. I was definitely expecting resistance from the positivists who feel that everything must end neatly with a p-value. However, in this crowd, there was agreement that true value would be added by developing a reasonable extension to the existing checklist so that authors could be guided through weaving their equity relevant findings into their reports.
But why does equity matter in systematic reviews? And in whose systematic reviews? If you have not been following the ongoing discussion around equity in reviews, I recommend reading Tugwell et al. (2010) which explains how systematic reviews of health generally demand an equity lens so that impacts might be viewed across different groups within populations and in order to understand those differences that are unfair and able to be remedied. Without attention to equity in reviews, we run the risk of averaging out the effect without understanding how the intervention might work differently for different groups. Equity is an important step towards unpacking the black box that is so many interventions.
However, the new PRISMA Equity Extension will not be released until perhaps August at the earliest. There is still wordsmithing to be done. More so, for those of us who work in systematic reviews that focus on development interventions. We will be waiting to apply this guideline to our work both for the planning of reviews and for the reporting, so that decision makers in health, economics, environmental issues, education, and social welfare will have the opportunity to look at how these interventions are reaching target populations in developing countries.
Tracey Koehlmoos is programme head for health and family planning systems at ICDDR,B and adjunct professor at the James P Grant School of Public Health, BRAC University, Dhaka, Bangladesh.