This section of the website includes useful resources and tools. A trio of guidance for COS development now exists, in addition to the COMET Handbook. Click the links below for more information.



The Core Outcome Set-STAndards for Development (COS-STAD) identifies minimum standards for the design of a COS study, and can be used to help users decide whether a COS is relevant and has been developed using a reasonable approach.



The Core Outcome Set-STAndardised Protocol Items (COS-STAP) Statement consists of a checklist of items considered essential in a COS protocol.

COS-STAP Reporting Checklist template



The Core Outcome Set-STAndards for Reporting (COS-STAR) provides guidance for the final reporting of COS development studies.

COS-STAR Reporting Checklist template

The COMET Handbook: version 1.0


This Handbook, developed by the COMET Initiative, brings together current thinking and methodological research regarding COS development, implementation, evaluation and updating. We recommend a four-step process to develop a COS.

We aim to update the contents of the Handbook in 2022. For an up-to-date list of research since the publication of V1.0 of the Handbook, please click here. If you know of any newly published methods research in COS development or uptake that are not on this list, please let us know.

Online consensus meetings for COS development: issues to consider

This guidance document summarises the key issues to consider for COS developers who are holding online consensus meetings. Click here to download.