The COMET (Core Outcome Measures in Effectiveness Trials) initiative

Article type
Authors
Williamson P1, Altman D2, Blazeby J3, Clarke M4, Gargon E1
1University of Liverpool, UK
2University of Oxford, UK
3University of Bristol, UK
4Queens University Belfast, UK
Abstract
Background: Systematic reviews are hampered by inconsistencies in outcomes assessed and reported in otherwise eligible studies. Many meta-analyses have to exclude key studies because relevant outcomes were not reported. Much could be gained if an agreed minimum set of appropriate and important outcomes was measured and reported in all clinical trials in a particular area.

Why standardise outcomes? The design of new trials would be simplified, their risk of measuring inappropriate outcomes would be reduced, and selective reporting of outcomes would be less likely. It would be easier to compare, contrast and combine studies in systematic reviews, and the choice of primary and secondary outcomes for reviews would be more straightforward. Core outcome sets would help review authors to present their findings clearly and succinctly, for example within Summary of Findings tables.

Aims: COMET initiative brings together researchers interested in standardised outcome sets, with well-attended international meetings in 2010 and 2011. COMET aims to foster and facilitate research by providing guidance on developing a core outcome set, methods to include user involvement in this process, and preparing reporting standards for such projects. Work is ongoing to identify, collate and maintain relevant resources in a searchable database on the internet. More than 50 completed projects in various areas of health/health care have been identified. Several examples of planned and ongoing work have also been recorded. The database will be demonstrated and progress to date will be presented.

Implications for The Cochrane Collaboration and systematic reviews: If successful, COMET will help review authors choose outcomes, and will increase the likelihood that these outcomes have been measured in eligible studies, thereby decreasing the likelihood of important studies being excluded. By improving the evidence base for reviews, COMET will make it easier for people to make well-informed decisions in health care.