A Pilot Randomized Trial of Rumination-tailored Feedback in Guided Internet-based CBT-I for University Students

This study is a pilot randomized controlled trial with three parallel arms. Participants will be randomly assigned to either (1) guided internet-based cognitive behavioral therapy for insomnia (iCBT-I), (2) guided iCBT-I with additional rumination-tailored, rule-based personalized feedback, or (3) a waitlist control group. The study aims to evaluate the feasibility and preliminary efficacy of integrating targeted cognitive feedback into a digital insomnia intervention.

The study will recruit university students with clinically relevant insomnia symptoms. Participants will be included if they are university students, 18 years of age or older, fluent in Persian and able to read and understand online study materials, reporting clinically relevant insomnia symptoms, and willing to complete online questionnaires and use the internet-based intervention platform.

Participants will be excluded if they have a current severe psychiatric condition requiring immediate treatment, such as psychosis, mania, or active suicidal intent; are currently receiving another structured insomnia treatment or CBT-I program; have a diagnosed sleep disorder other than insomnia that would better explain the sleep problem, such as sleep apnea, restless legs syndrome, or narcolepsy; work regular night shifts or have a highly irregular sleep-wake schedule that would make the intervention unsuitable; have a substance use problem severe enough to interfere with participation; or have a cognitive or language problem that prevents completion of the online materials or questionnaires.

The base intervention consists of a structured guided internet-based CBT-I program including standard components such as sleep restriction, stimulus control, cognitive restructuring, sleep hygiene education, and relaxation techniques. Participants receive weekly brief supportive guidance during the intervention period (for intervention arms only).

In the experimental condition, participants additionally receive rumination-tailored, rule-based personalized feedback generated based on their levels of repetitive negative thinking and sleep-related cognitive arousal. The feedback is predefined according to decision rules and is not dynamically generated. The feedback targets repetitive negative thinking patterns, sleep-related worry and cognitive arousal, and maladaptive pre-sleep cognition. Feedback is delivered in written format alongside standard CBT-I guidance and is designed to complement, not replace, core therapeutic components.