## 3 Results
### Post-Questionnaire for Therapists  
The therapists positively mentioned the video call function and the possibility of treating patients after the clinical stay. The most criticized point by the therapists was exercise preparation. It took them a lot of time to implement exercises in the system, and it was not possible to automatically include exercises from PDF files.  
The most used features of the system were exercise creation for the patients, activity monitoring, and the video call function. The therapists learned to use the system in less than two hours. Six of the therapists reported that the instruction to the system was sufficient (note: it was about 1 h of instruction). The introduction of the system to the patients took approximately 0.5-1 h and was sufficient, according to the therapists.  
The quality of the combined therapy concept compared with conventional therapy was rated as good, with quality improvements through the possibility of treating the patient after discharge from the clinic. It was also clearly mentioned that it is still necessary to hold face-to-face sessions as these cannot be replaced by video calls alone.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Usefulness** & \begin{tabular}{c} **Ease of Use and** \\ **Learability** \\ \end{tabular} & \begin{tabular}{c} **Interface** \\ **Quality** \\ \end{tabular} & \begin{tabular}{c} **Interaction** \\ **Quality** \\ \end{tabular} & \begin{tabular}{c} **Reliability** \\ \end{tabular} & \begin{tabular}{c} **Satisfaction and** \\ **Future Use** \\ \end{tabular} & \
\begin{tabular}{c} **Intention to** \\ **Use** \\ \end{tabular} \\ \hline
\begin{tabular}{c} Mean-Therapists \\ (\(n=7\)) \\ Mean-Patients \\ (\(n=3\)) \\ \end{tabular} & 4.9 & 6.0 & 5.3 & 5.1 & 3.4 & 5.5 & 5.0 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Usability Comparison between Therapists and Patients.  
Asked about the practicability of the combined therapy concept in daily work, the therapists clearly stated that it would be necessary to have extra time for this kind of treatment. Positively mentioned were time savings compared with conventional therapy. The preparation of exercises was the most time-consuming task. However, it offers the potential for exercises to be used for multiple patients, leading to much more efficient exercise planning. In general, the combined therapy concept could lead to a more efficient treatment of patients by using asynchronous training and video calls, according to five therapists.  
Five therapists mentioned the possibility of aftercare treatment at home as the main advantage. Further advantages mentioned by single therapists are higher motivation, an easy-to-use system, the inclusion of the home setting in the therapy, time-saving due to less traveling, a combination of face-to-face and synchronous therapy, and the possibility to adjust the therapy easily. The greatest disadvantage mentioned by four therapists is the lack of control during the patient's training (correct movements, changes in the patient's state).  
All therapists stated that their patients definitely trained more with the system than without it. Estimations of some therapists reached up to twice the training frequency with the system. All therapists except one saw the tablet with the exercises as a significant motivating factor for the patients to continue their training and exercise. Regarding Pablo, therapists stated that motivation increased in their patients. Positively mentioned was the activity monitoring, where the performance of the patients was visible and supported tracking the progress.