Literature list.

Background
With increasing attention to core outcome sets (COS), the number of studies on COS for respiratory diseases (COS-RD) is on the rise. However, the methodological quality is still unclear. Therefore, we conducted a study to assess the methodological quality of studies on COS-RD.
Methods
PubMed, Embase, Cochrane Library, and Web of Science were searched for study protocols or original studies on COS-RD about adults, from their inception to February 23, 2024. The COMET database and Chinese databases (including China National Knowledge Infrastructure, Wanfang Data, Chongqing VIP database, and China Biology Medicine) were also searched as a supplement. Two researchers independently screened the literature, extracted the data, and assessed the methodological quality of included studies using the Core Outcome Set-STAndardised Protocol (COS-STAP) statement, the Core Outcome Set-STAndards for Development (COS-STAD) recommendations, and the Core Outcome Set-STAndards for Reporting (COS-STAR) statement.
Results
A total of 27 articles (five study protocols and 22 original studies, 26 studies) were included in this study. For the assessment of study protocols using the COS-STAP statement, the item with the lowest complete reporting rate was "missing data" (Item 9, 40.0%), while "description how outcomes may be dropped/combined, with reasons" (Item 5b, 60.0%) and "dissemination" (Item 11, 60.0%) had relatively low complete reporting rates. For the assessment of original studies using the COS-STAD recommendations, the item with the highest non-reporting rate was "care was taken to avoid ambiguity of language used in the list of outcomes" (Item 11, 45.5%), while "the population(s) covered by COS" (Item 3, 31.8%) and "the intervention(s) covered by COS" (Item 4, 31.8%) had relatively high non-reporting rate. When using the COS-STAR statement to assess the original studies, the item with the lowest complete reporting rate was "protocol deviations" (Item 11, 13.6%), while “describe how outcomes were dropped/combined, with reasons (if applicable)” (Item 6b, 36.4%), "participants" (Item 5, 40.9%), "ethics and consent" (Item 10, 54.5%), "protocol/registry entry" (Item 14, 63.6%), and “outcome scoring” (Item 8, 63.6%) had relatively low complete reporting rates.
Conclusion
The methodological quality of studies on COS-RD needs to be further improved. The appropriate use of aforementioned international reporting standards can advance the methodological quality and reporting transparency of studies on COS-RD.

研究背景
随着对核心结局量表（core outcome sets, COS）关注度的不断提升，针对呼吸系统疾病核心结局量表（COS-RD）的相关研究数量呈上升趋势。然而，此类研究的方法学质量仍尚不明确。为此，本研究旨在评估COS-RD相关研究的方法学质量。

研究方法
本研究检索了PubMed、Embase、Cochrane图书馆及Web of Science数据库，检索时限为各数据库建库至2024年2月23日，检索内容为针对成人的COS-RD相关研究方案或原始研究。同时补充检索COMET数据库，以及中国知网（China National Knowledge Infrastructure）、万方数据、重庆维普数据库、中国生物医学文献数据库（China Biology Medicine）等中文数据库。由2名研究者独立完成文献筛选与数据提取，并分别采用《核心结局量表标准化方案报告规范》（Core Outcome Set-STAndardised Protocol, COS-STAP）、《核心结局量表研制规范指南》（Core Outcome Set-STAndards for Development, COS-STAD）以及《核心结局量表报告规范》（Core Outcome Set-STAndards for Reporting, COS-STAR）对纳入研究的方法学质量进行评价。

研究结果
本研究共纳入27篇文献，其中包括5项研究方案及22项原始研究，合计26项研究。采用COS-STAP规范对研究方案进行质量评价时，完整报告率最低的条目为「缺失数据」（第9条，40.0%），「描述结局指标的剔除/合并方式及理由」（第5b条，60.0%）与「传播计划」（第11条，60.0%）的完整报告率也相对偏低。采用COS-STAD指南对原始研究进行质量评价时，未报告率最高的条目为「注意避免结局指标列表中语言表述的歧义性」（第11条，45.5%），「核心结局量表覆盖的研究人群」（第3条，31.8%）及「核心结局量表覆盖的干预措施」（第4条，31.8%）的未报告率相对较高。采用COS-STAR规范对原始研究进行质量评价时，完整报告率最低的条目为「方案偏离情况」（第11条，13.6%），「描述结局指标的剔除/合并方式及理由（如适用）」（第6b条，36.4%）、「研究对象」（第5条，40.9%）、「伦理与知情同意」（第10条，54.5%）、「方案注册/数据库登记」（第14条，63.6%）及「结局指标评分」（第8条，63.6%）的完整报告率均相对偏低。

研究结论
当前COS-RD相关研究的方法学质量仍有待进一步提升。合理应用上述国际报告规范，可有效改善COS-RD相关研究的方法学质量与报告透明度。