[Psychotherapy for obsessive-compulsive disorder: what is evidence based?].

Obsessive-compulsive disorder is a severe, very disabling condition that usually takes a chronic course if no adequate treatment is applied. Up to now, cognitive behavioural therapy with exposure and response prevention (CBT) is the most thoroughly investigated and most effective intervention, leading to a clinically significant symptom reduction in 60-70% of the patients. Correctly applied, this treatment can be equally effective as its combination with pharmacological management. For a correct implementation, however, several points have to be considered which are described in the following review. Considering the fact that some of the patients are unable to benefit sufficiently from this approach, potential alternatives and extensions of CBT are discussed. To date, however, no other treatment approach has proven to be effective based on randomised controlled trials.