Supplementary Material for: Selective outcome reporting bias in randomized controlled trials on dental caries in children and adolescents: A meta-research study

Introduction. Selective Outcome Reporting (SOR) is a type of bias that potentially manifests in Randomized Controlled Trials (RCTs) and is defined as the change or omission of the primary outcome in the publication compared to the protocol. Researchers may alter outcomes to emphasize statistical significant results. We aimed to assess the prevalence of SOR in RCTs related to dental caries in Pediatric Dentistry.

Methods. We conducted a search on the ClinicalTrials.gov and International Clinical Trials Registry Platform (ICTRP), using a comprehensive search strategy that included terms related to pediatric dentistry and dental caries, up to February 2023. Two independent reviewers included any trial that had two or more arms and focused on dental caries in pediatric dentistry. We excluded any registration that did not result in at least one published article. Data such as study characteristics and outcome data were extracted. The chi-square test was used with a significance level set at 5% to detect the association between SOR and the pre-specified variables.

Results. One hundred and forty-four protocols and their corresponding publications were included. SOR was observed in 58.9% (n=103), and 41.1% (n=72) having discrepancies in the primary outcome follow-up. Retrospectively registered studies accounted for 73.7%. SOR was significantly associated with discrepancies in the follow-up period (p

引言。选择性结果报告（Selective Outcome Reporting，简称SOR）是一种可能出现在随机对照试验（Randomized Controlled Trials，简称RCTs）中的偏差，其定义为在出版物中与方案相比，主要结果的变化或省略。研究者可能会更改结果以强调统计上的显著性。本研究旨在评估儿科牙科学中与龋齿相关的RCTs中SOR的普遍性。

方法。我们在ClinicalTrials.gov和国际临床试验注册平台（International Clinical Trials Registry Platform，简称ICTRP）上进行了检索，检索策略包括与儿科牙科学和龋齿相关的术语，截止至2023年2月。两位独立的审阅者纳入了具有两个或更多臂且专注于儿科牙科学龋齿的任何试验。我们排除了未导致至少一篇已发表文章的注册。提取了诸如研究特征和结果数据等信息。使用卡方检验，显著性水平设定为5%，以检测SOR与预指定的变量之间的关联。

结果。纳入了144个方案及其相应的出版物。观察到SOR占58.9%（n=103），41.1%（n=72）在主要结果随访中存在差异。回顾性注册的研究占73.7%。SOR与随访期的差异显著相关（p