An analysis of how many units needs to be included are based on 12+12 clusters. Two calculations have been performed. The first calculation is based on how big is the reduction in use of restraints. We assume in our model that there will be a 60 % reduction in use of restraints in the intervention group and 33 % reduction in the control group (Hawthorne effect). For this reason we need to include averagely 13 patients in each department/unit in order to achieve a statistical power of 0,8.