Importance: Digital cognitive behavioral therapy for insomnia (DCBT-I) requires adaptation to different sociocultural contexts. Moreover, studies comparing DCBT-I and sleep education in the same operating interface are lacking.
Objective: To investigate the efficacy of a smartphone-based Chinese culture-adapted DCBT-I application (app) for insomnia compared with sleep education using the same app.
Design, setting, and participants: This was a single-blinded, randomized clinical trial conducted from March 2021 to January 2022. Screening and randomization were conducted at Peking University First Hospital. Follow-up visits were performed online or in the same hospital. After assessing for eligibility, eligible participants were enrolled and allocated (1:1) to DCBT-I or sleep education groups. Data were analyzed from January to February 2022.
Interventions: A Chinese smartphone-based app with the same interface was used in both DCBT-I and sleep education groups over 6 weeks, with 1-, 3-, and 6-month follow-ups.
Main outcomes and measures: The primary outcome was Insomnia Severity Index (ISI) scores with the intention-to-treat principle. Secondary and exploratory outcomes included sleep diary measures; self-reported scales assessing dysfunctional beliefs about sleep, mental health, and quality of life; and smart bracelet measures.
Results: Of 82 participants (mean [SD] age, 49.67 [14.49] years; 61 [74.4%] females), with 41 randomized to sleep education and 41 randomized to DCBT-I; 77 participants completed the 6-week intervention (39 participants in the sleep education group and 38 participants in the DCBT-I group; full analysis data set) and 73 completed the 6-month follow-up (per protocol data set). Mean (SD) ISI scores in the DCBT-I group were significantly lower than those in the sleep education group after the 6-week intervention (12.7 [4.8] points vs 14.9 [5.0] points; Cohen d = 0.458; P = .048) and at the 3-month follow-up (12.1 [5.4] points vs 14.8 [5.5] points; Cohen d = 0.489; P = .04). There were significant improvements from before to after the intervention for both the sleep education and DCBT-I groups, with large effect sizes(sleep education: d = 1.13; DCBT-I: d = 1.71). Some of the sleep diary measures and self-reported scales showed more improvements in the DCBT-I group than sleep education group, such as total sleep time (mean [SD]: 3 months, 403.9 [57.6] minutes vs 363.2 [72.3] minutes; 6 months, 420.3 [58.0] minutes vs 389.7 [59.4] minutes) and sleep efficiency (mean [SD]: 3 months, 87.4% [8.3%] vs 76.7% [12.1%]; 6 months, 87.5% [8.2%] vs 78.1% [10.9%]).
Conclusions and relevance: In this randomized clinical trial, the smartphone-based Chinese culture-adapted DCBT-I improved insomnia severity compared with sleep education. Future multicenter clinical trials with large sample sizes are needed to validate its effectiveness in the Chinese population.
Trial registration: ClinicalTrials.gov Identifier: NCT04779372.