Study Objectives: Our aim was to compare the effects of Internet-delivered cognitive therapy (CT) and behavior therapy (BT) against a waitlist (WL) condition to better understand their unique contribution in the treatment of insomnia.

Methods: Two hundred and nineteen participants with insomnia disorder were randomized to CT (n = 72), BT (n = 73), or WL (n = 74). The treatment arms consisted of 10 weekly internet-delivered modules with 15 min of telephone support per week. At pre, post, and follow-up, participants completed measures of insomnia severity, sleep diaries, functional impairment, anxiety, depression, quality of life, adverse events, satisfaction and perception of content, workload, and activity in treatment. Measures of completed exercises, modules, therapist support, and platform logins were also measured at posttreatment.

Results: Moderate to large effect sizes for both CT and BT outperformed the WL on the majority of outcomes, with significant differences in favor of both therapy groups. Both treatment groups had significantly larger proportion of treatment remitters (CT: 35.8%, BT: 40%, WL: 2.7%) and responders (CT: 74.6%, BT 58.6%, WL: 10.8%) compared to the WL at posttreatment. There were no significant differences between the two therapy groups in terms of outcomes, except for sleep onset latency in favor of BT (6 min difference at posttreatment) and adverse events in favor of CT (CT 14.1% vs BT 43.2%).

Conclusions: This study indicates that both Internet-delivered CT and BT are effective as stand-alone therapies for insomnia disorder. Results highlight the need for examining which therapy and subcomponents that are necessary for change.

ClinicalTrials.gov Identifier: NCT02984670

Introduction: Little is known about what pretreatment patient characteristics the outcome of Cognitive Therapy (CT) and Behavioral Therapy (BT) for insomnia disorder depends on. Identifying for whom treatment is most useful is essential for treatment optimization and personalized care. Therefore, this investigation aimed to examine both theory-driven constructs and insomnia-associated clinical variables as potential predictors and moderators of outcomes in CT and BT.

Materials and methods: One hundred forty-five participants diagnosed with insomnia disorder were randomly assigned to 10 weekly internet-delivered modules of CT or BT, along with 15 min of weekly telephone support. General clinical predictors and theory-driven moderators (cognitive and behavioral processes) assessed in a previous randomized controlled trial were analyzed using multiple linear regression, with insomnia severity as the outcome.

Results: Bedtime variability and early morning awakening interacted with treatment and indicated that lower bedtime variability and early morning awakening were associated with a higher effect for CT, whereas the opposite was true for BT. Wake time after sleep onset, insomnia severity index, and sleep efficiency emerged as predictors, indicating prognostic value for treatment outcome.

Conclusions: In addition to identifying three insomnia-associated variables as predictors of outcome across both treatments, this trial showed that CT and BT could be differentially effective based on patient insomnia heterogeneity at baseline. The differential moderator findings are in line with the theoretical models of CT and BT and might clinically implicate the ability to match therapy to patient features to optimize outcomes.

Objective: To examine if the processes in the cognitive model mediate cognitive therapy (CT) and behavior therapy (BT) for insomnia.

Method: Individuals diagnosed insomnia disorder (n=219) were randomized to telephone supported internet-delivered cognitive therapy (n=72), behavior therapy (n=73), or a waitlist (n=74). Cognitive processes (worry, dysfunctional beliefs, monitoring and safety behaviors) proposed to maintain insomnia and treatment outcome (insomnia severity; ISI) were assessed biweekly. Criteria for evaluating mediators were assessed via parallel process growth modeling and cross-lagged panel models.

Results: Parallel process growth modeling showed that dysfunctional beliefs, monitoring and safety behaviors significantly mediated the effects of both CT and BT. Cross-lagged panel models confirmed that dysfunctional beliefs and monitoring, which approached significance, drove the change for CT. In BT, however, prior changes in ISI predicted later changes in worry and monitoring, and reciprocal influences among processes and outcomes were observed for dysfunctional beliefs and safety behaviors. The effect of safety behavior on outcome was significantly larger for BT compared to CT.

Conclusion: Together, the findings support the role of dysfunctional beliefs and monitoring as processes of change in CT, and safety behaviors as a specific mediator in BT. Limited evidence was provided for worry as a mediator. These findings have relevance for the conceptualizations of insomnia, future research, and clinical management.