To improve the consistency of outcome documentation and address the potential for outcome reporting bias in clinical trials involving integrative Chinese and Western medicine (ICWM) for ulcerative colitis (UC), we aim to develop a customized core outcome set (COS) that incorporates input from various stakeholders. The study design of this COS has been informed by the Core Outcome Measures in Effectiveness Trials Initiative Handbook, with adherence to the guidelines from the Core Outcome Set-STAndards for Reporting statement and Core Outcome Set-STAndardised Protocol Items recommendations. Five groups of stakeholders will be invited to participate in the development of COS for clinical trials with ICWM for UC, including healthcare professionals, patients, COS developers, COS users, and methodologists. The process will involve five stages: (1) conducting a systematic review of outcomes reported in clinical trials and protocols to develop a list of potential outcome domains; (2) conducting semi-structured interviews to obtain important outcomes; (3) choosing the most important outcomes by conducting three-round Delphi surveys; (4) achieving a consensus in a face-to-face meeting to discuss the final COS; and (5) publication, dissemination and implementation of COS. Consequently, this specialized COS will be applicable to clinical trials involving both traditional Chinese medicine (TCM) and ICWM interventions. Please cite this article as: Zhang X, Zhang L, Wang J, Lau CT, Wang N, Zhang X, Wang P, Li J, Han F, Bian Z. A protocol for developing, disseminating and implementing a core outcome set for clinical trials of integrative Chinese and Western medicine for ulcerative colitis. J Integr Med. 2025; 23(6):654-659.

Key words: Consensus study, Core outcome set, Delphi method, Integrative Chinese and Western medicine, Ulcerative colitis