Improvements and advances in core outcome set methodology: proceedings of the CS-COUSIN & COMFA Joint Meeting.

A COS is a systematically developed list of outcomes recommended for reporting all studies within a particular disease area. The Cochrane Skin-Core Outcome Set Initiative (CS-COUSIN) and the Core Outcome Measures in Food Allergy (COMFA) Initiative Joint Meeting was held virtually on September 23 through 28, 2021. This meeting brought together core outcome set (COS) developers within the domains of dermatology and food allergy, respectively. The meeting assessed the state of COS methodology, provided a forward look, and facilitated the networking of members of individual COS groups. The meeting hosted several expert-led key addresses and focus sessions, in which work was critically discussed, new developments were shared, and groundwork was laid for future projects. The conference emphasized the importance of ongoing COS work to improve patient outcomes and limit research waste.