Weekly brief phone support in self-help cognitive behavioral therapy for insomnia disorder: Relevance to adherence and efficacy.

Self-help cognitive-behavioral therapy for insomnia (CBT-I) is an acceptable, low-intensity treatment in a stepped care model for insomnia. We tested the application of self-help CBT-I in a Chinese population. 312 participants with self-report of insomnia associated with distress or daytime impairment 3 or more nights per week for at least 3 months were randomized to self-help CBT-I with telephone support (SHS), self-help CBT-I (SH) and waiting-list (WL). The program was Internet-based with treatment materials delivered once per week, and lasted for 6 consecutive weeks, while the telephone support was limited to 15 min weekly. Mixed-effects analyses found significant group by time interaction in sleep and sleep-related cognitions at immediate and 4-week posttreatment. Post-hoc pairwise comparison with WL revealed that both SHS and SH had significantly higher sleep efficiency at immediate (p = .004 and p = .03, respectively) and 4-week posttreatment (p = .002 and p = .02, respectively) and lower insomnia and dysfunctional beliefs scores. The SHS group had additional improvements in sleep onset latency and sleep quality. Benefits with self-help CBT-I were maintained at 12-week posttreatment, but attrition rate was about 35%. Internet-based self-help CBT-I was effective and acceptable for treating insomnia in the Chinese population. A brief telephone support further enhanced the efficacy.