I read with great interest the ChONdroitin versus CElecoxib versus Placebo Trial (CONCEPT) by Reginster et al. 1 I would like to raise some worthwhile issues that need to be clarified. The authors concluded that 800 mg/day pharmaceutical-grade chondroitin sulfate (CS) is similar to celecoxib in improving pain and function after 6 months in patients with symptomatic knee osteoarthritis (OA).1 However, the interpretation of similarity between these two active treatments was not based on the analysis of the data. Because, the authors did not assess whether these treatments are similar by equivalence analysis. Rather, the authors assessed the superiority between these two active treatments by aiming to detect a difference in intention-to-treat (ITT) populations—although the study might not be powered to be able to detect differences between these two active treatments (type 2 error), since sample size is calculated to show superiority of CS over placebo; and they failed to show a difference between CS and celecoxib. According to the Consolidated Standards of Reporting Trials 2010 statement on reporting of non-inferiority and equivalence randomised trials, ’Failure to show a difference does not mean they are equivalent. By contrast, …

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Reginster 等人对 CONCEPT 的评论：数据分析支持作者的解释吗？

我非常感兴趣地阅读了 Reginster 等人的 ChONdroitin vs CElecoxib vs Placebo Trial (CONCEPT)。1 我想提出一些需要澄清的有价值的问题。作者得出结论，800 毫克/天的药物级硫酸软骨素 (CS) 与塞来昔布在改善症状性膝关节骨性关节炎 (OA) 患者 6 个月后的疼痛和功能方面相似。1 然而，这两种积极治疗之间相似性的解释不是基于对数据的分析。因为，作者没有通过等效性分析评估这些治疗是否相似。相当，作者通过旨在检测意向治疗 (ITT) 人群的差异来评估这两种积极治疗之间的优越性——尽管该研究可能无法检测这两种积极治疗之间的差异（2 型错误） ，因为计算样本量以显示 CS 优于安慰剂；并且他们未能显示 CS 和塞来昔布之间的差异。根据 2010 年报告试验合并标准关于报告非劣效性和等效性随机试验的声明，“未能显示差异并不意味着它们是等效的。相比之下， … 根据 2010 年报告试验合并标准关于报告非劣效性和等效性随机试验的声明，“未能显示差异并不意味着它们是等效的。相比之下， … 根据 2010 年报告试验合并标准关于报告非劣效性和等效性随机试验的声明，“未能显示差异并不意味着它们是等效的。相比之下， …