Internet-delivered CBT intervention (Space for Sleep) for insomnia in a routine care setting: Results from an open pilot study

Insomnia is a highly prevalent, often comorbid disorder associated with difficulties sleeping, remaining awake, and impaired quality of life. Internet-delivered Cognitive Behavioral Therapy for insomnia (ICBT-I) has the potential to help large numbers of people with sleep disorders. This study investigated the preliminary effects of an 8-week guided ICBT-I intervention within a routine stepped-care service. Fifty-six (N = 56) patients consented to participate. The primary outcome was assessed using the Insomnia Severity Index (ISI) and secondary outcome measures included the Patient Health Questionnaire 9-item (PHQ-9), Generalized Anxiety Disorder 7-item (GAD-7), and the Work and Social Adjustment Scale (WSAS), each administered at baseline and weekly thereafter. Intention-to-treat analyses indicated that ICBT-I produced statistically significant pre- to post- reductions in symptoms of insomnia, yielding within-group effects of d = 0.82 suggesting a potential for improved outcomes. Similar improvements were seen across secondary outcomes, with small-to-medium post-treatment within-group effects observed: depression (d = 0.63), anxiety (d = 0.39), and functional impairment (d = 0.31). These findings are supportive of the intervention's potential effectiveness and speak to the importance of several implementation factors that could enhance the effects of the intervention. The results contribute to the growing evidence base for digital interventions designed to help those with sleep difficulties and will inform the design of a future controlled evaluation of ICBT-I under routine clinical settings.