Core Outcome Set-STAndards for Development: The COS-STAD recommendations

Background
The use of core outcome sets (COS) ensures that researchers measure and report those outcomes that are most likely to be relevant to users of their research. Several hundred COS projects have been systematically identified to date, but there has been no formal quality assessment of these studies. The Core Outcome Set-STAndards for Development (COS-STAD) project aimed to identify minimum standards for the design of a COS study agreed upon by an international group, while other specific guidance exists for the final reporting of COS development studies (Core Outcome Set-STAndards for Reporting [COS-STAR]).
Methods and findings
An international group of experienced COS developers, methodologists, journal editors, potential users of COS (clinical trialists, systematic reviewers, and clinical guideline developers), and patient representatives produced the COS-STAD recommendations to help improve the quality of COS development and support the assessment of whether a COS had been developed using a reasonable approach. An open survey of experts generated an initial list of items, which was refined by a 2-round Delphi survey involving nearly 250 participants representing key stakeholder groups. Participants assigned importance ratings for each item using a 1–9 scale. Consensus that an item should be included in the set of minimum standards was defined as at least 70% of the voting participants from each stakeholder group providing a score between 7 and 9. The Delphi survey was followed by a consensus discussion with the study management group representing multiple stakeholder groups. COS-STAD contains 11 minimum standards that are the minimum design recommendations for all COS development projects. The recommendations focus on 3 key domains: the scope, the stakeholders, and the consensus process.
Conclusions
The COS-STAD project has established 11 minimum standards to be followed by COS developers when planning their projects and by users when deciding whether a COS has been developed using reasonable methods.

研究背景
核心结局量表（Core Outcome Sets, COS）的使用可确保研究者测量并报告最贴合研究使用者需求的结局指标。截至目前，已有数百项核心结局量表相关项目被系统梳理识别，但尚未有针对这些研究的正式质量评估。核心结局量表开发标准（Core Outcome Set-STAndards for Development, COS-STAD）项目旨在确定一套由国际专家组共同认可的核心结局量表研究设计最低标准，而针对核心结局量表开发研究的最终报告则已有其他专项指南：《核心结局量表报告标准》（Core Outcome Set-STAndards for Reporting, COS-STAR）。

方法与结果
由经验丰富的核心结局量表开发者、方法学家、期刊编辑、核心结局量表潜在使用者（临床试验研究者、系统综述研究者与临床指南制定者）以及患者代表组成的国际工作组制定了COS-STAD推荐意见，以助力提升核心结局量表开发质量，并辅助评估某一核心结局量表是否采用合理方法开发。研究通过开放专家调研生成初始条目清单，随后开展两轮德尔菲调研对条目进行优化，本次调研共有近250名代表各关键利益相关方群体的参与者参与。参与者采用1-9分制为每个条目赋值重要性评分。当某一利益相关方群体中至少70%的投票参与者给出7-9分的评分时，即认定该条目应被纳入最低标准清单。德尔菲调研结束后，工作组联合代表多利益相关方群体的研究管理小组开展共识研讨。COS-STAD共包含11项最低标准，为所有核心结局量表开发项目提供了最低设计推荐意见。该推荐意见聚焦三大核心领域：研究范围、利益相关方参与以及共识制定流程。

结论
COS-STAD项目确立了11项最低标准，供核心结局量表开发者在项目规划阶段遵循，同时供核心结局量表使用者在评估某量表是否采用合理方法开发时作为参考依据。