Sleep problems among adolescent survivors following the 2008 Wenchuan earthquake in China: a cohort study.

Objective: To examine sleep problems and associated risk factors among adolescent survivors following the 2008 Wenchuan earthquake, the deadliest earthquake to strike China in 30 years.

Method: A cohort of students (N = 1,573) in the 7th and 10th grades from Dujiangyan City, 21 kilometers from the epicenter, was followed up periodically for 2 years. Participants were assessed at 12 months (n = 1,398; May 18-22, 2009), 18 months (n = 1,288; November 23-27, 2009), 24 months (n = 1,313; May 17-21, 2010), and 30 months (n = 1,038; November 22-26, 2010) after the earthquake.