Table 4.
Frequency and severity of problems encountered during the completion processes for all participants.
| Problem | Number of participants who encountered the problem | Number of times the problem occurred | Severity rating |
| 1. Accidentally skipping a screen by double-tapping the “next” button | 2 | 2 | Low |
| 2. Double-tapping an answering option causing activation and deactivation of the answer of choice | 0 | 0 | —a |
| 3. Skipping a screen by accidentally touching the next button with the palm of the hand | 0 | 0 | — |
| 4. Not using the navigation function of the photo gallery in question 4 causing the participant to not see all response items | 5 | 22 | Serious |
| 5. Touching the text under a photo in question 4 to select an activity, instead of touching the photo itself, causing the activity not to be selected | 4 | 10 | Critical |
| 6. Not able to see whether or not a selected answer is activated (not accentuated enough) | 1 | 1 | Low |
| 7. Not knowing how to get to the next screen | 0 | 0 | — |
| 8. Pushing too hard or tapping too softly on the touch screen so that it does not respond | 8 | 19 | Serious |
| 9. Not able to correct a wrong answer | 3 | 3 | Medium |
| 10. Not reading the text above the photos in question 5, causing the participant to continue the task given in question 4 | 1 | 1 | Low |
| 11. Not noticing that the multiple numeric rating scale “effort” scores in question 8 are related to different activities, which in error results in identical scores for different activities | 1 | 1 | Low |
| 12. Mistakenly scoring the mirror image in the body chart in question 2 | 1 | 1 | Low |
| 13. Scoring (serial) questions that do not apply to the participants’ situation (forced by the software) | 0 | 0 | — |
| 14. Using navigation function question 4 to try to get to the next screen. | 2 | 2 | Low |
| 15. Not knowing how to enter an answer into the TTSQb | 2 | 2 | Medium |
| 16. Not being aware of the existence of the “help” function | 2 | 2 | Medium |
| 17. Entering more than one answer into an NRSc causing the TTSQ to select only the last entered answer | 2 | 2 | Low |
| 18. Activating the “stop” function accidentally by touching it with the palm of the hand holding the tablet | 1 | 2 | Medium |
aThis problem was found in the study on the Duth Talking Touch Screen Questionnaire [20], not in this study.
bTTSQ: Talking Touch Screen Questionnaire.
cNRS: Nummeric Rating Scale