LAUSR

We conducted an exploratory study to identify risk factors of dropout in an 8-week e-mail-based cognitive-behavioral therapy for insomnia (REFRESH) to improve sleep among university students with insomnia symptoms. University and graduate students in Hong Kong and Korea who scored higher than 10 on the Insomnia Severity Index participated in REFRESH. Of 158 participants from Hong Kong (n = 43) and Korea (n = 115), 90 (57%) did not complete all 7 sessions, while 52 of 90 (57.8%) dropped out prior to the fourth session. ROC analysis was conducted on the entire sample of 158 participants with intervention completion vs. dropout (non-completion) as the outcome variable. Predictors of dropout were wake time after sleep onset (WASO) < 7.1 min on the weekly sleep diary and expectations for sleep (a subscale of dysfunctional beliefs and attitudes about sleep; DBAS) < 18 at baseline. These findings indicate that shorter WASO and less expectations for sleep at baseline were associated with risk of dropout from e-mail delivered self-help CBT-I-based intervention. Our results highlight the importance of identifying and tailoring treatment formats to students based on their presenting sleep characteristics.