3.5.1 Target Acquisition Task Measures The performance during the target acquisition task was measured by different quantitative variables: target selection time, error rate, and overall task completion time. This data was collected automatically by the prototype application running on the mobile phone. Each participant was asked to perform one run consisting of 90 targets that they were supposed to select by touching them with their thumb. Distance between two consecutive targets varied and was either 31.5 mm and 42.5 mm.
In summary, the study design was:
16 Participants x
90 Targets x
4 Settings (1 standing + 3 walking conditions)
= 5760 measures overall