Table 1 Study aims and criteria of success

a) To achieve an average patient recruitment rate of three patients per month.

Within 13 months of study duration 49 patients could be screened and 41 patients could be assessed and randomised. This corresponds to a recruitment rate of 3.2 to 3.8 patients per month.

b) To be able to recruit patients with an ischemic or hemorrhagic stroke and to evaluate if patients' body weight limit up to 90 kg is manageable for assessors.

In total 29 patients with an ischemic and 10 patient with a hemorrhagic stroke participated in the study. One patient exceeded a body weight of 90 kg. Management of patients with this high body weight level depends on the motor function ability and therefore, on the level of help needed rather than on the weight itself.

c) To be able to perform the motor task with 90% of all patients.

In total, 40 of 41 patients were able to perform the motor task at BL. At T0, T1, and FU all patients were able to perform the motor task.

a) 90% of patients per group understand and perform the required MI intervention in the provided dosage and frequency.

All patients understood and performed the required MI intervention. One patient in EG1 could not perform the complete embedded MI intervention during the first and second session. Due to time constrains one patient in EG2 did receive only two of six intervention sessions.

b) 90% of patients were able to perform all assessments in the given time frame and procedure for all measurement events.

The applied assessment procedure was feasible for all patients. The required time frame up to 3 hours at BL was tolerated due to short breaks.

c) A sample size calculation could be performed based on the obtained assessments regarding time in seconds needed to perform the motor task.

Based on the collected data, a sample size calculation for a subsequent phase III trial and a post hoc power for the pilot study could be performed based on the primary outcome measure time needed to perform the motor task.