Outcome will be measured using the AVL (aggression questionnaire) and the SDAS (social dysfunction and aggression scale) after 2, 4, 6, 8, and 10 weeks of treatment. Change on the CGI (Clinical Global Impression) will be compared to baseline. As usual at the study-site, the SOAS-R (Staff Observation Aggression Scale) will be filled in in case of violent incidents and type, number and duration of restraining interventions will be registered. Also recorded will be symptoms occurring during treatment and number and cause of dropout.