O026 Digital CBT for insomnia: does who and how matter?

Abstract Introduction Cognitive behavioural therapy for insomnia (CBT-I) is the gold-standard treatment for chronic insomnia. Digital approaches (dCBT-I) enhance accessibility and offer comparable effectiveness, with the option of self- or clinician-guided formats. It remains unclear whether the type of supporting clinician influences outcomes. This study examined whether changes in sleep disturbance (Insomnia Severity Index; ISI) and psychological distress (Kessler Psychological Distress Scale; K-10) were predicted by delivery format and clinician type. Methods Participants included 9567 Australian adults with insomnia who commenced a 4-lesson d-CBTI program in self- (n = 6206) or clinician-guided (n = 3361) formats. Clinicians included general practitioners (GP; n = 2156), medical specialists (n = 507), nurses (n = 35), psychologists (n = 510), social workers (n = 43), other allied health (n = 101), and other (n = 9). Results Improvements in ISI and K-10 scores were observed across both delivery formats, although ISI reductions were greater in the self-guided group (p=.004). Interestingly, both delivery format and clinician type predicted baseline K-10, but not ISI. Specifically, the clinician-guided group reported higher baseline K-10 than the self-guided group (p<.001), especially those supervised by psychologists versus GPs (p<.001) or medical specialists (p<.001). Despite this, supervising clinician did not predict changes in ISI or K-10 over time. Discussion Overall, self- and clinician-guided dCBT-I effectively reduces sleep disturbance and psychological distress, underscoring the importance of digital sleep interventions. Whilst baseline psychological distress was higher among those supported by psychologists, clinician type did not impact outcomes over time. Given the current shortage of CBT-I-trained clinicians, upskilling a broader clinician base could improve access without comprising on effectiveness.