Applying therapist-guided digital cognitive behavioral therapy for insomnia in psychiatry a mixed-methods process evaluation

Introduction: Insomnia is prevalent, particularly among individuals with mental health complaints. However, Cognitive Behavioral Therapy for Insomnia (CBT-I), the first-line treatment, is underutilized in care settings. This study evaluated a therapist-guided digital CBT-I (i-Sleep), gathering insights from participants and therapists to optimize the intervention and inform implementation strategies. Methods: A mixed-methods process evaluation, guided by the RE-AIM framework, was conducted alongside an effectiveness trial. Data were collected from i-Sleep participants with clinically relevant insomnia and various mental health complaints across all care levels, ranging from pre-clinical (unattended), to those referred to general or specialized care. Additionally, data were collected from i-Sleep therapists. Results: A total of 181 i-Sleep participants (mean age = 46.7 years, SD = 13.2) enrolled, with an attrition rate of 21.6%. Participants reported benefits including faster sleep onset, fewer nighttime awakenings, increased daytime energy, and positive lifestyle changes, though some experienced minimal gains or adverse effects. Satisfaction with the intervention ranged from 7.1 to 7.3 across care levels. Post-intervention, 89.4% of all participants indicated they would recommend iCBT-I. Satisfaction with therapist guidance was high (M = 7.7–8.3), though preferences for format and frequency varied. Therapists (n = 15, mean experience = 0.8 years, SD = 1.1) suggested addressing practical constraints and enhancing training for better integration into routine care. Conclusion: Our findings highlight the feasibility and potential of therapist-guided iCBT-I to improve sleep in individuals with mental health complaints across all care settings. Universal implementation could offer significant benefits, while adaptable content and flexible guidance may better meet individual needs. Trial registration: Netherlands Trial Register (NL9776) registered on 07/10/2021.