Depression is a major public health concern. Emerging research has shown that cognitive behavioral therapy for insomnia (CBT-I) is effective in treating individuals with comorbid insomnia and depression. Traditional face-to-face CBT-I encounters many obstacles related to feasibility, accessibility, and help-seeking stigma. CBT-I delivered via smartphone application could be a potential solution. This two-arm parallel randomized controlled trial (RCT) aims to examine the effectiveness of a smartphone-based self-help CBT-I with a waitlist control group in treating people with major depression and insomnia in Hong Kong.~Participants complete an online rapid screening, followed by a telephone diagnostic interview. Those who meet the eligibility criteria are randomized in a ratio of 1:1 to receive either CBT-I immediately or to a waitlist control condition. The CBT-I consists of six weekly modules and is delivered through a smartphone application known as proACT-S. An online randomized algorithm is used to perform randomization to ensure allocation concealment. The primary outcomes are changes over the measurement points in sleep quality, insomnia severity and depression severity. The secondary outcomes include changes over the measurement points in anxiety, subjective health, treatment expectancy, and acceptability of treatment. Assessments are administered at baseline, post-intervention, and 6-week follow up. The recruitment is underway. Important adverse events, if any, are documented. Multilevel linear mixed model based on intention-to-treat principle will be conducted to examine the effectiveness of the CBT-I intervention~Participants in the CBT-I condition will start CBT-I immediately after randomization; while participants in the waitlist control group will start CBT-I (equivalent to that of the CBT-I group) immediately after completing the post-intervention assessment. It is hypothesized that, after the intervention, participants in the CBT-I condition will report a greater decrease in poor sleep quality, depression severity and insomnia severity than those in the waitlist control condition. It is also hypothesized that the reduction in poor sleep quality, depression severity and insomnia severity observed in the CBT-I condition will be maintained at 6-week follow-up. Furthermore, it is hypothesized that participants in the waitlist control condition will report a significant decrease in poor sleep quality, depression severity and insomnia severity after receiving CBT-I.
This randomized controlled trial aims to examine the effectiveness of a self-help smartphone-delivered cognitive behavioral therapy for insomnia, compared to a waitlist control, in treating people with major depression and insomnia in Hong Kong.