Negative body image is a common public health concern among adolescents, globally. The aim of the current study was to evaluate the effectiveness, implementation fidelity, and acceptability of a single session, school-based universal body image intervention in Indonesia. A total of 1926 adolescents (59.4 % girls) and 12 school guidance counsellors (lesson facilitators) from nine state junior secondary schools in Surabaya, East Java took part in a two-arm open parallel cluster randomised controlled trial. In response to the changing circumstances due to the COVID-19 pandemic, half of the lessons were conducted in person and half were delivered online. Results showed that the lesson did not significantly improve adolescent body image or secondary outcomes relative to the control, though there was no evidence of harm. There were no substantive findings regarding intervention effectiveness by gender. The mode of intervention delivery (online vs. in-person) did not significantly influence the main findings. Implementation fidelity varied widely, and the lesson content and pedagogy were largely acceptable, though there was a strong preference for in-person lesson delivery. Findings have implications for researchers aiming to improve adolescent body image in low- and middle-income countries. Lessons learned can inform future school-based efforts to support adolescent body image.

中文翻译：

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评估印度尼西亚学校的身体形象课程：一项随机对照试验

负面的身体形象是全球青少年普遍关注的公共卫生问题。本研究的目的是评估印度尼西亚单次、基于学校​​的通用身体形象干预措施的有效性、实施保真度和可接受性。来自东爪哇泗水九所公立初中的总共 1926 名青少年（59.4% 是女孩）和 12 名学校辅导员（课程辅导员）参加了一项双臂开放平行集群随机对照试验。为了应对新冠肺炎 (COVID-19) 大流行造成的情况变化，一半的课程是面对面授课，一半是在线授课。结果显示，与对照组相比，该课程并没有显着改善青少年的身体形象或次要结果，尽管没有证据表明有害。没有关于按性别划分的干预效果的实质性调查结果。干预实施方式（在线与面对面）并没有显着影响主要发现。实施保真度差异很大，课程内容和教学法在很大程度上是可以接受的，尽管人们强烈倾向于面对面授课。研究结果对旨在改善低收入和中等收入国家青少年身体形象的研究人员具有重要意义。吸取的经验教训可以为未来以学校为基础的支持青少年身体形象的努力提供参考。