Peer victimization is a worldwide crisis unresolved by 50 years of research and intervention. We capitalized on recent methodological advances and integrated self-determination theory with a social-ecological perspective. We provided teachers with a professional development experience to establish a highly supportive classroom climate that enabled the emergence of pro-victim student bystanders during bullying episodes. In our longitudinal cluster randomized control trial, we randomly assigned 24 teachers (15 men, 9 women; 19 middle school, 5 high school; 32.8 years old, 6.7 years of experience) in 48 classrooms to the autonomy-supportive teaching (AST) workshop (24 classrooms) or the no-intervention control (24 classrooms). Their 1,178 students (age: M = 13.7, SD = 1.5; range = 11-18) reported their perceived teacher autonomy support; perceived classmates' autonomy support; adoption of the defender role; and peer victimization at the beginning, middle, and end of an 18-week semester. A doubly latent multilevel structural equation model with follow-up mediation tests showed that experimental-group teachers created a substantially more supportive classroom climate, leading student bystanders to embrace the defender role. This classroom-wide (L2) emergence of pro-victim peer bystanders led to sharply reduced victimization (effect size = -.40). Unlike largely unsuccessful past interventions that focused mainly on individual students, our randomized control trial intervention substantially reduced bullying and victimization. Focusing on individual students is likely to be ineffective (even counterproductive) without first changing the normative climate that reinforces bullying. Accordingly, our intervention focused on the classroom teacher. In the classrooms of these teachers, bystanders supported the victims because the classroom climate supported the bystanders. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

中文翻译：

---

减少同伴受害的整群随机对照试验：支持自主的教学干预改变了课堂风气，以支持保护旁观者。

同伴受害是一场世界性危机，经过 50 年的研究和干预仍未得到解决。我们利用最新的方法论进展，将自决理论与社会生态学视角相结合。我们为教师提供专业发展经验，以建立高度支持的课堂氛围，使欺凌事件中出现支持受害者的​​学生旁观者。在我们的纵向整群随机对照试验中，我们随机分配 48 个教室的 24 名教师（15 名男性，9 名女性；19 名初中，5 名高中；32.8 岁，6.7 年经验）参加自主支持教学（AST）研讨会（24 间教室）或无干预控制（24 间教室）。他们的 1,178 名学生（年龄：M = 13.7，SD = 1.5；范围 = 11-18）报告了他们感知到的教师自主支持；感知同学的自主支持；采取辩护人的角色；以及在 18 周的学期开始、中期和结束时的同伴受害情况。具有后续中介测试的双潜多级结构方程模型表明，实验组教师创造了一种更加支持性的课堂氛围，引导学生旁观者接受辩护者角色。这种在课堂范围内（L2）出现的亲受害者同伴旁观者导致受害人数急剧减少（效应大小 = -.40）。与过去主要针对个别学生的不成功干预措施不同，我们的随机对照试验干预措施大大减少了欺凌和受害行为。如果不首先改变强化欺凌行为的规范氛围，那么关注个别学生可能是无效的（甚至适得其反）。因此，我们的干预重点是课堂老师。在这些老师的教室里，旁观者支持受害者，因为课堂气氛支持旁观者。（PsycInfo 数据库记录 (c) 2023 APA，保留所有权利）。