## 3 Results
### Test Questionnaires
#### 3.2.2. Use  
Then, the user can start using the system. Usually, its operation is driven by a piece of software, so the user needs to switch on the device and eventually a related application to pair the system, personalize some settings, and activate some functions. For this, several tasks/subtasks related to global operation could be identified. The most frequently adopted usability scoring method is the SUS tool that fits well with the usability assessment of wearable systems and is a questionnaire composed of 10 items in order to assess the perceived usability of technological systems. In any case, a proper amount of usage time must be considered before administering the test in order to have a consistent usability assessment. Otherwise, and in some cases this should be considered, the usability analysis should be split into two phases: (a) after the first usage (to investigate the intuitiveness of the interface and its functions) and (b) after 2/3 days/1 week (to better explore the overall usability).  
Specific and quantitative measures of the system's efficiency, such as successful task completion and the related time, could also be taken. For example, the wearable system must carry out or support some functions; in this case, simple, logical, and immediate scores can be introduced, such as:  
* Successful completion of the operation: binary value 0/1 (N/Y);
* Rate of the level of received assistance: VAS 0-10 (value with one decimal);
* Time in seconds to complete the action, measured with two decimals;  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Item Score** &
\begin{tabular}{c} **Expected Wearability (Considering both** \\ **Wearing and Removing the System)** \\ \end{tabular} & **Expected Comfort** \\ \hline
1 & very difficult & very bad \\
2 & difficult & bad \\
3 & neutral & neutral \\
4 & easy & good \\
5 & very easy & very good \\ \hline \hline \end{tabular}
\end{table}
Table 2: Scoring table for the pre-test questionnaire for the factors with their semantic meaning and the corresponding value of 1–5 in the Likert scale system.  
In addition, some subjective evaluations could be recorded on these aspects through some dedicated questionnaires using a Likert-scale-based scoring method in accordance with the proper semantic meaning (Table 3).  
At the end of this phase, the assessment of the overall comfort/discomfort though the methods described in the previous step (the 0-100 VAS scale and the BPD chart) should be repeated. Again, a blank space for free text and notes could be given to report free observations or suggestions on how to improve usability.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Item Score** & \
\begin{tabular}{c} **Appropriateness of the** \\ **Received Support** \\ \end{tabular} &
\begin{tabular}{c} **Importance of the Received** \\ **Support** \\ \end{tabular} \\ \hline
1 & very negative & not important at all \\
2 & negative & not important \\
3 & slightly negative & slightly not important \\
4 & neutral & neutral \\
5 & slightly positive & slightly important \\
6 & positive & important \\
7 & very positive & very important \\ \hline \hline \end{tabular}
\end{table}
Table 3: Scoring table for the pre-test questionnaire for the factors with their semantic meaning and the corresponding value of 1–7 in the Likert scale system.  
Figure 2: The comfort scoring charts system: (**a**) the 0–100 VAS scale to report a general comfort assessment and (**b**) the body part discomfort chart to report the eventually perceived discomfort in specific body areas and its intensity level.