摘要 : Objective: To determine whether school start time changes impact adolescents mood, self-regulation, safety, and health.Methods: In September 2015, two school start time changes were implemented in Fairfax County (VA) Public School... 展开 Objective: To determine whether school start time changes impact adolescents mood, self-regulation, safety, and health.Methods: In September 2015, two school start time changes were implemented in Fairfax County (VA) Public Schools: a 50-minute delay (to 8:10 am) for high schools and secondary schools and a 30-minute advance (to 7:30 am) for middle schools. We conducted cross-sectional surveys of students' sleep, mood, self-regulation, health, and safety before (2017 students) and after (1180 students) these changes. 收起