Pilot evaluation of the Sleep Ninja: a smartphone application for adolescent insomnia symptoms

OBJECTIVES: The aim of this study was to test the feasibility, acceptability and preliminary effects of a recently developed smartphone application, Sleep Ninja, for adolescent sleep difficulties. SETTING: The study was conducted online with Australian individuals recruited through the community. PARTICIPANTS: Participants were 50 young people aged 12–16 years with sleep difficulties. DESIGN: A single-arm pre–post design was used to evaluate feasibility, acceptability and sleep and mental health variables at baseline and postintervention. INTERVENTION: Cognitive–behavioural therapy for insomnia informed the development of the Sleep Ninja. The core strategies covered by the app are psychoeducation, stimulus control, sleep hygiene and sleep-related cognitive therapy. It includes six training sessions (lessons), a sleep tracking function, recommended bedtimes based on sleep guidelines, reminders to start a wind-down routine each night, a series of sleep tips and general information about sleep. Users progress through each training session and conclude the 6-week programme with a black belt in sleep. OUTCOME MEASURES: Feasibility was evaluated based on consent rates, adherence and attrition, acceptability was assessed using questionnaires and a poststudy interview, and sleep, depression and anxiety variables were assessed at baseline and postintervention. RESULTS: Data indicated that the Sleep Ninja is a feasible intervention and is acceptable to young people. Findings showed that there were significant improvements on sleep variables including insomnia (within-group effect size d=−0.90), sleep quality (d=−0.46), depression (d=−0.36) and anxiety (d=−0.41). CONCLUSIONS: The Sleep Ninja is a promising intervention that could assist adolescents who experience sleep difficulties. A follow-up randomised controlled trial is now warranted. TRIAL REGISTRATION NUMBER: ACTRN12617000141347