Investigating the Effects of the Unified Protocol on Common and Specific Factors in a Comorbid Insomniac Sample: A Single-Case Experimental Design

Background: Insomnia and emotional disorders share common factors that underlie and perpetuate these disorders. The Unified Protocol (UP) for transdiagnostic treatment of emotional disorders is a new treatment approach designed to target core processes of emotional disorders. Objectives: The present study examined the effects of UP on behavioral inhibition/behavioral activation, anxiety sensitivity, and emotion dysregulation as transdiagnostic factors, as well as cognition and behaviors specific to insomnia, in a small sample of patients (N = 6) with comorbid insomnia and emotional disorders. Methods: A multiple-baseline across subjects single-case experimental design with a 3-month follow-up was used. Participants were allocated to 2, 4, and 6 baseline periods and then received 14 weekly individual sessions of UP. The outcome measures were Behavioral Inhibition/Behavioral Activation Scales (BIS/BAS), Anxiety Sensitivity Index-3 (ASI-3), Difficulties in Emotion Regulation Scale (DERS), Dysfunctional Beliefs and Attitudes about Sleep Scale-10 (DBAS-10), and Sleep-Related Behaviors Questionnaire (SRBQ). Data were analyzed using visual inspection, mixed model analysis, and reliable change index (RCI). Results: Mixed model analysis showed significant changes in BIS/BAS, ASI-3, DERS, DBAS-10, and SRBQ from pre-treatment to posttreatment. Most participants achieved a reliable change in BIS, ASI-3, DERS, DBAS-10, and SRBQ at a 3-month follow-up. Conclusions: This preliminary study provides empirical evidence on the utility of UP for reducingcommonvulnerability and sleepspecific factors in chronic insomnia comorbid with emotional disorders. Further research is needed to test these findings in randomized controlled studies.