App-based conversational agents for tinnitus distress and mental health: A randomised controlled trial.

Tinnitus is often accompanied by anxiety, depression, insomnia, and significant psychological distress, highlighting the need for accessible, evidence-based interventions. Internet-delivered cognitive behavioural therapy (iCBT) offers a scalable and standardised approach, and chatbots provide an emerging mode of automated delivery. This randomised controlled trial investigated the effectiveness of two app-based iCBT interventions for adults with persistent tinnitus (N = 105). Participants were randomly allocated to one of three conditions for eight weeks: a tinnitus-specific iCBT chatbot (Tinnibot), a general iCBT chatbot for mood and anxiety (Woebot), or a waiting-list control group. Outcomes were assessed at baseline and post-intervention and included tinnitus-related distress (Tinnitus Functional Index; primary outcome), anxiety (Generalised Anxiety Disorder Scale), depression (Patient Health Questionnaire), insomnia (Insomnia Severity Index), mindfulness (Mindful Attention Awareness Scale), and life satisfaction (Satisfaction with Life Scale). Analyses used mixed analysis of variance with an intention-to-treat approach. Both chatbot groups showed significant improvements in anxiety and depression relative to the control group. Tinnibot also produced significant improvements in insomnia severity. Tinnitus distress decreased in both chatbot groups, but only Tinnibot achieved a clinically meaningful reduction. Changes in mindfulness and life satisfaction were modest and did not differ between groups. These findings indicate that chatbot-delivered iCBT can improve comorbid symptoms associated with tinnitus, and that tinnitus-specific tailoring confers additional, clinically meaningful benefits for tinnitus distress.