Core Outcome Set–STAndards for Reporting: The COS-STAR Statement

Abstract

BackgroundCore outcome sets (COS) can enhance the relevance of research by ensuring that outcomes of importance to health service users and other people making choices about health care in a particular topic area are measured routinely. Over 200 COS to date have been developed, but the clarity of these reports is suboptimal. COS studies will not achieve their goal if reports of COS are not complete and transparent.Methods and FindingsIn recognition of these issues, an international group that included experienced COS developers, methodologists, journal editors, potential users of COS (clinical trialists, systematic reviewers, and clinical guideline developers), and patient representatives developed the Core Outcome Set–STAndards for Reporting (COS-STAR) Statement as a reporting guideline for COS studies. The developmental process consisted of an initial reporting item generation stage and a two-round Delphi survey involving nearly 200 participants representing key stakeholder groups, followed by a consensus meeting. The COS-STAR Statement consists of a checklist of 18 items considered essential for transparent and complete reporting in all COS studies. The checklist items focus on the introduction, methods, results, and discussion section of a manuscript describing the development of a particular COS. A limitation of the COS-STAR Statement is that it was developed without representative views of low- and middle-income countries. COS have equal relevance to studies conducted in these areas, and, subsequently, this guideline may need to evolve over time to encompass any additional challenges from developing COS in these areas.ConclusionsWith many ongoing COS studies underway, the COS-STAR Statement should be a helpful resource to improve the reporting of COS studies for the benefit of all COS users.

A Core Outcome Set for Multimorbidity Research (COSmm)

“…12 We used the Core Outcome Set-STAndards for Reporting (COS-STAR) Equator Network guidelines for the reporting of this core outcome set. 1 Core outcome sets can be considered in terms of what to measure, which we refer to as outcomes, and how to measure it, which we refer to as metrics. 13 …”

“…22 A range of consensus process methods have been used to develop various core outcome sets. 1 We chose to use a Delphi panel approach on the basis of our previous experience and a review of core outcome set literature. 19,21,23 Other potential approaches include expert panel groups, nominal group techniques, semistructured group discussions, and questionnaires.…”

“…Other core outcome sets have been developed using alternative outcome-scoring methods, which may have been more appropriate. 1 These alternatives include use of a higher number of Likert scale options, scoring based on average agreement scores, and a ranking system. The methodology for developing core outcome sets has been evolving rapidly over the last few years, and there is no clear evidence as yet on which is the best scoring method.…”

“…org/). 1 Core outcome sets represent the minimum that should be measured and reported in all clinical trials of a specific condition or conditions. 1 Multimorbidity is commonly defined as the coexistence of 2 or more chronic conditions in an individual.…”

“…1 Core outcome sets represent the minimum that should be measured and reported in all clinical trials of a specific condition or conditions. 1 Multimorbidity is commonly defined as the coexistence of 2 or more chronic conditions in an individual. 2 Its effects include reduced healthrelated quality of life, increased psychological distress, functional difficulties, increased health care use, and heightened mortality risk.…”