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Psychol Med. 2014 Oct;44(13):2877-87. doi: 10.1017/S0033291714000543. Epub 2014 Mar 14.

Long-term efficacy of Internet-based cognitive behavior therapy for obsessive-compulsive disorder with or without booster: a randomized controlled trial.

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Department of Clinical Neuroscience, Division of Psychiatry,Karolinska Institutet,Stockholm,Sweden.
Department of Clinical Neuroscience, Division of Psychology,Karolinska Institutet,Stockholm,Sweden.



As relapse after completed cognitive behavior therapy (CBT) for obsessive-compulsive disorder (OCD) is common, many treatment protocols include booster programs to improve the long-term effects. However, the effects of booster programs are not well studied. In this study, we investigated the long-term efficacy of Internet-based CBT (ICBT) with therapist support for OCD with or without an Internet-based booster program.


A total of 101 participants were included in the long-term follow-up analysis of ICBT. Of these, 93 were randomized to a booster program or no booster program. Outcome assessments were collected at 4, 7, 12 and 24 months after receiving ICBT.


The entire sample had sustained long-term effects from pre-treatment to all follow-up assessments, with large within-group effect sizes (Cohen's d = 1.58-2.09). The booster group had a significant mean reduction in OCD symptoms compared to the control condition from booster baseline (4 months) to 7 months, but not at 12 or 24 months. Participants in the booster group improved significantly in terms of general functioning at 7, 12 and 24 months, and had fewer relapses. Kaplan-Meier analysis also indicated a significantly slower relapse rate in the booster group.


The results suggest that ICBT has sustained long-term effects and that adding an Internet-based booster program can further improve long-term outcome and prevent relapse for some OCD patients.

[Indexed for MEDLINE]

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