The difference between treatment and usual care group was analyzed univariately by log rank tests, and Kaplan-Meier curves were plotted. A Cox proportional hazard model was applied to analyze the difference between groups, also accounting for age, sex, diagnostic category at admission, and days at the ICU. We took the time at the general ward for patients who were treated at the General Hospital Vienna until discharge, and the total time at the general ward (days at the General Hospital Vienna + other hospital) for patients who were treated at the General Hospital Vienna and then transferred to another hospital. For some patients, the event (discharge from the general ward) did not occur within the observation period, as they were either lost to follow up (that means they were transferred to another hospital with unknown LOS) or died. For these patients we took the time at the general ward of the General Hospital Vienna until transfer or until death, respectively, and censored them. In the statistical analyses, the censoring considered that these patients did not experience the event (discharge from the general ward) until the time of censoring. No assumption was made when it may have happened afterwards. The intention to treat sample included five censored patients (3 early rehabilitation group, 2 usual care group) and the per protocol sample three censored patients (1 early rehabilitation group, 2 usual care group).