The Core Outcome Measures in Effectiveness Trials (COMET) Working Group has published a series of research and reporting guidelines related to core outcome sets since it was established. This article introduces and interprets the Core Outcome Set-STAndardised Protocol Items: the COS-STAP Statement which is developed by the COMET and published in February 2019. It will then be compared with Core Outcome Set-STAndards for Reporting (COS-STAR) and Core Outcome Set-STAndards for Development (COS-STAD), which have been introduced to China. The significance of these guidelines for the development of core outcomes in the field of traditional Chinese medicine is discussed, so as tp draw researchers' attention to this area.