Breaking the sleep tunnel: effects of a single-session scarcity-informed mass psychoeducation on dysfunctional beliefs and insomnia symptoms.

STUDY OBJECTIVES: Cognitive-behavioral therapy for insomnia (CBT-I) effectively targets dysfunctional sleep beliefs but remains inaccessible to most. This study examined whether a single 60-minute mass psychoeducation session, incorporating Scarcity Theory with CBT-I psychoeducation elements and Acceptance and Commitment Therapy concepts, could reduce dysfunctional beliefs and insomnia symptoms over 4 weeks. MATERIALS AND METHODS: This prospective, single-arm study was conducted at Seoul National University Bundang Hospital. Of 182 lecture attendees, 81 consented, 40 completed baseline and immediate post-lecture assessments, and 29 completed all four timepoints through 4 weeks. The primary outcome was the Korean Dysfunctional Beliefs and Attitudes about Sleep-6 (K-DBAS-6). Secondary outcomes included the Insomnia Severity Index-3 (ISI-3), Bandwidth Tax Visual Analogue Scale (BT-VAS), and Patient Global Impression measures. Longitudinal effects were analyzed using repeated measures ANOVA (N = 29). RESULTS: K-DBAS-6 decreased significantly (d z = 0.63, p = .003). ISI-3 (d z = 0.60, p = .003), BT-VAS (d z = 0.62, p = .002), and PGI-S (d z = 0.97, p < .001) also improved. BT-VAS showed immediate post-lecture reduction (d z = 0.63, p < .001; N = 40). At 4 weeks, 72.4% reported global improvement (PGI-I ≤ 3). Anchor-based minimal clinically important differences were 1.32 (K-DBAS-6), 1.58 (ISI-3), and 1.83 (BT-VAS). All effects remained significant after adjusting for age and sex. CONCLUSIONS: A single mass psychoeducation session informed by Scarcity Theory produced significant, sustained reductions in dysfunctional sleep beliefs and insomnia symptoms with medium effect sizes. This scalable approach warrants investigation as a first-step intervention for insomnia.