Youth with intellectual disability (ID) are at an increased risk of displaying fewer prosocial behaviors and more numerous aggressive behaviors in various environments. This study proposes a new multi-informant (youth, teachers, and parents) measure of social behaviors for youth with ID. The sample includes 348 youth with mild (51.41%) and moderate (48.59%) levels of ID, aged 11–22 years old (M = 15.73, SD = 2.14; including 138 females), enrolled in secondary schools in Canada (French-speaking; N = 116; 33.33%) and Australia (English-speaking; N = 232; 66.67%). Measures were completed by the participants, their teachers, and their parents. Results support the reliability, factor validity, discriminant validity (in relation to sex, ID level, and country), concurrent validity (with measures of victimization, depression, hyperactivity-inattention), and one-year test–retest stability of the measure. Youth, teachers, and parents all provided a complementary perspective on youth social behaviors, consistent with youth adjusting their behaviors to the various environments in which they share social interactions.

智障 (ID) 青年在各种环境中表现出更少的亲社会行为和更多的攻击性行为的风险增加。本研究提出了一种新的多线人（青年、教师和父母）衡量智障青年社会行为的方法。样本包括 348 名患有轻度 (51.41%) 和中度 (48.59%) ID 的青年，年龄在 11-22 岁（M  = 15.73，SD  = 2.14；包括 138 名女性），在加拿大（法国-说；N  = 116；33.33%）和澳大利亚（说英语；N = 232; 66.67%）。措施由参与者、他们的老师和他们的父母完成。结果支持该测量的信度、因子效度、判别效度（与性别、ID 水平和国家相关）、并发效度（包括受害、抑郁、多动-注意力不集中的措施）和一年测试-再测试稳定性。青年、教师和家长都对青年社会行为提供了互补的观点，这与青年根据他们分享社交互动的各种环境调整自己的行为是一致的。