Efficacy of a web application as a self-help intervention for nightmares: a randomized controlled trial
Julia Voss, Madlen Peters, Gordon Pipa, Katharina Lüth
Somnologie - Schlafforschung und Schlafmedizin April 30, 2026 DOI: 10.1007/s11818-026-00550-w (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 42 |
| Population | People with recurrent nightmares (at least every 2 weeks) |
| Duration | 8-week intervention |
| Topics | Dreaming |
| Keywords | Randomized controlled trial Intervention counseling Distress Cognitive behavioral therapy Intention-to-treat analysis Clinical trial Psychological intervention Physical therapy Clinical psychology |
| Key findings | DreamMend significantly reduced nightmare frequency and distress compared to a waitlist control over 8 weeks. |
Abstract
Abstract Background Approximately 5% of people suffer from nightmares at least every 2 weeks. One cognitive behavioral intervention for recurrent nightmares is imagery rehearsal therapy (IRT), in which individuals recall, modify, and rehearse a less distressing version of their dream.
Objective: This randomized controlled trial evaluated the efficacy of a web application called “DreamMend” as a self-help method for reducing nightmares and their associated burden. It delivers digital IRT via an artificial intelligence (AI)-powered chatbot. Materials and methods A total of 42 participants were randomized to the intervention ( n = 18) or control group ( n = 24). The intervention group received access to DreamMend for 8 weeks. Analyses were conducted in 34 participants with available outcome data (intervention: n = 16; control: n = 18).
Results: Nightmare frequency in the intervention group decreased over the course of 8 weeks, while it remained constant in the control group. Linear mixed models (LMMs) revealed a statistically significant time × group interaction, showing that the intervention group profits from the intervention. Nightmare distress decreased in both groups over the 8 weeks. The LMMs revealed a significant time × group interaction, indicating that the intervention group experienced a significantly more marked decrease in distress.
Conclusion: The DreamMend web-based application significantly reduced nightmare frequency, distress, and overall nightmare burden compared with a waitlist control, even with variable adherence and minimal intervention exposure. These findings demonstrate that AI-supported digital IRT is a feasible and effective self-help intervention. Larger, more diverse trials are needed to confirm efficacy and examine long-term outcomes.