Booster as an Adjunct to Internet-based Cognitive Behavior Therapy (CBT)

Study Overview
=================
Brief Summary
-----------------
In this trial, we test if adding an Internet-based booster program to regular Internet-based cognitive behavior therapy (ICBT) is effective for patients with obsessive-compulsive disorder (OCD).

Detailed Description
-----------------
Written consent form. Completing ICBT in our previous study: Please see NCT01347099 for more details.

Official Title
-----------------
Efficacy of an Internet-based Booster Program for Obsessive-compulsive Disorder: A Randomized Controlled Trial

Conditions
-----------------
Obsessive-compulsive Disorder

Intervention / Treatment
-----------------
* Behavioral: Booster


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Signed consent Previously enrolled in our randomized controlled trial testing ICBT for OCD: NCT01347099 Exclusion Criteria: Suicidal ideation that could jeopardize participation

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control group<br>No offer of booster program. | |
| Experimental: Booster<br>3 week booster program + 2 additional weeks two months later for follow-up. | Behavioral: Booster<br>* 3 week booster program + 2 additional weeks two months later for follow-up.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline of obsessions and compulsions after 3, 8 and 20 months after baseline. | Yale Brown Obsessive Compulsive Scale (Y-BOCS). Analysis will examine the frequency of relapse from remission between the groups. Furthermore, frequency of incremental cases of remission will be compared between the groups. | 3 months before treatment, 3 weeks after treatment starts, 6 and 18 months after treatment has ended | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline of obsessions and compulsions after 8 and 20 months. | Obsessive Compulsive Scale - Revised (OCI-R) | 3 months before treatment, 6 and 18 months after treatment has ended | 
| Change from Baseline of obsessions and compulsions after 8 and 20 months. | Trimbos Institute Cost-assessment for Psychiatry (TIC-P) | 3 months before treatment, 6 and 18 months after treatment has ended | 
| Change from Baseline of obsessions and compulsions after 8 and 20 months. | Montgomery Asberg Depression Rating Scale | 3 months before treatment, 6 and 18 months after treatment has ended | 
| Change from Baseline of obsessions and compulsions after 8 and 20 months. | Euroqol | 3 months before treatment, 6 and 18 months after treatment has ended | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
booster program, internet, cbt, Study the specific effects of adding a booster program