Sample size A power calculation has been made, based on the primary outcome variable, number of days in hospital. Based on a former similar study in a slightly younger population there will be an assumed difference between the intervention group and the control group of 4,1 days in hospital in 24 months (11,1 days in the intervention group and 15,2 in the control group) with standard deviation of 15 days in both groups. To be able to detect a difference between the intervention and the control groups with a two-sided test and with a significance level of α=0.05 and 80% power, at least 211 participants in each group will be needed. There will be almost no loss to follow-up of of this outcome based on previous research of this patient-group and intervention, so a total of 450 persons will be included.