BACKGROUND AND AIMS Selective outcome reporting occurs when trialists prespecify primary and secondary outcomes during trial planning but alter the definitions in the published report. Here, we investigate selective outcome reporting in published addiction randomized controlled trials (RCTs) and evaluate whether particular funding sources are associated with an increased likelihood of selective outcome reporting. DESIGN We conducted a cross-sectional study of published addiction clinical trials. A PubMed search was performed to identify RCTs in addiction journals from 2013 to 2017. Included studies used a randomized design to address one of the following topics: (1) drug, alcohol, and tobacco addiction prevention, (2) stabilization following excessive use of a substance, (3) relapse prevention, or (4) recovery maintenance. SETTING Single-center, medical research institution. PARTICIPANTS Our sample included 162 RCTs that were prospectively registered with a clearly defined primary outcome. MEASUREMENTS We extracted the following items from addiction RCTs: journal, funding source, trial registry number (if included), sample size, dates of subject enrollment, whether primary and secondary outcomes were denoted, all published outcomes, P-value for all outcomes, and whether authors mentioned any deviations from the trial protocol as it related to RCT outcomes. FINDINGS In total, 47 of 162 RCTs (29.0%) had at least one major discrepancy between the trial registry and published RCT. Overall, these 47 RCTs included 56 major discrepancies. The most common major discrepancy was demotion of a primary registered outcome (19/56, 33.9%). The majority of RCTs (132/162, 81.5%) were funded from public sources. Additionally, 166 RCTs were excluded from our sample because registration could not be confirmed. CONCLUSIONS There is evidence suggestive of selective outcome reporting in addiction randomized controlled trials (RCTs). The most common major discrepancies pertained to the primary outcome.

中文翻译：

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成瘾临床试验中选择性结果报告和试验注册实践的评估

背景和目的 当试验者在试验计划期间预先指定主要和次要结果但改变已发表报告中的定义时，就会出现选择性结果报告。在这里，我们调查已发表的成瘾随机对照试验 (RCT) 中的选择性结果报告，并评估特定资金来源是否与选择性结果报告的可能性增加有关。设计 我们对已发表的成瘾临床试验进行了横断面研究。进行了 PubMed 搜索以识别 2013 年至 2017 年成瘾期刊中的 RCT。 纳入的研究使用随机设计来解决以下主题之一：（1）药物、酒精和烟草成瘾预防，（2）过度使用药物后的稳定性一种物质，（3）预防复发，或（4）恢复维持。设置单中心，医学研究机构。参与者 我们的样本包括 162 项前瞻性注册的随机对照试验，这些随机对照试验具有明确定义的主要结果。测量我们从成瘾 RCT 中提取了以下项目：期刊、资金来源、试验注册号（如果包括）、样本量、受试者入组日期、是否表示主要和次要结果、所有已发表的结果、所有结果的 P 值、以及作者是否提到了与试验方案的任何偏差，因为它与 RCT 结果有关。结果 总共 162 项 RCT 中的 47 项 (29.0%) 在试验注册与已发表的 RCT 之间存在至少一项重大差异。总体而言，这 47 项 RCT 包括 56 项主要差异。最常见的主要差异是主要注册结果的降级 (19/56, 33.9%)。大多数 RCT（132/162、81. 5%) 由公共资源资助。此外，由于无法确认注册，我们的样本中排除了 166 个 RCT。结论 有证据表明成瘾随机对照试验 (RCT) 中的选择性结果报告。最常见的主要差异与主要结果有关。