Study protocol for a randomised controlled trial of internet-based cognitive-behavioural therapy for...

Area of Science:

• Psychiatry and Mental Health
• Digital Therapeutics
• Clinical Psychology

Background:

• Obsessive-Compulsive Disorder (OCD) is a leading cause of disability, with Cognitive-Behaviour Therapy (CBT) being an effective treatment.
• Access to specialized CBT for OCD is limited by availability and social stigma.
• Internet-based CBT (iCBT) shows promise for anxiety disorders, with previous trials indicating efficacy for OCD.

Purpose of the Study:

• To conduct the first randomized controlled trial (RCT) of therapist-assisted iCBT for OCD compared to a matched control.
• To evaluate the efficacy and acceptability of therapist-assisted iCBT for OCD.
• To explore how patient characteristics influence treatment effectiveness.

Main Methods:

• A 12-week randomized controlled trial with 212 Australian adults diagnosed with OCD.
• Two arms: therapist-assisted iCBT (intervention) and therapist-assisted progressive relaxation training (iPRT) (control).
• Outcomes assessed at baseline, post-intervention, and six-month follow-up (for iCBT arm). Control group crosses over to iCBT post-intervention.

Main Results:

• Primary outcome: clinically significant change in obsessive-compulsive symptom scores.
• Secondary outcomes: acceptability of iCBT and influence of patient characteristics on effectiveness.
• Data collection at baseline, post-intervention, and six-month follow-up.

Conclusions:

• This trial is the first to compare therapist-assisted iCBT for OCD against a matched control intervention.
• Demonstrating iCBT efficacy can inform models for wider access to evidence-based OCD treatment.
• Findings will contribute to understanding the role of digital therapeutics in managing complex mental health conditions.