0240 VALIDATION OF A TOUCHSCREEN PSYCHOMOTOR VIGILANCE TASK FOR ANDROID DEVICES

Abstract

Introduction: The Psychomotor Vigilance Task (PVT) is a gold-standard, widely used, and highly sensitive tool to quantify effects of sleep loss. Current portable versions are either costly, not validated, or based on out-of-date platforms. Our goal was to develop a low-cost, widely accessible version of the PVT that runs on touchscreen devices. This study evaluated a new application (PVT-Touch), compared to the industry-standard PVT-192. Method(s): Subjects included N=44 healthy adults without symptoms of sleep disorders. They were administered the PVT-Touch and the standard PVT-192. Order of administration was block-randomized to ensure balanced presentation. Tests were 10 minutes each and administered in sequence. Mean and median reaction time (RT) and performance lapses (RT>500ms) were assessed and correlations were computed, with 95% confidence intervals. Regression analyses determined appropriate transforms that generated comparable scores. Following transforms, paired t-tests evaluated differences. Result(s): Despite differences in input style and device hardware, PVTTouch and PVT-192 values correlated highly for mean RT (r=0.83; 95%CI[0.71,0.91]; p<0.0001), median RT (r=0.82; 95%CI[0.70,0.90]; p<0.0001), and lapses (r=0.83; 95%CI[0.71;0.91]; p<0.0001). Perhaps due to input differences, though, the PVT-touch systematically produced longer reaction times, resulting in more lapses. To adjust for this difference, a correction factor (determined by regression analyses) of 0.75 was applied to PVT-Touch values. This resulted in no differences between groups, with t-test p values of 0.999 for mean and 0.953 for median. For lapses, a correction factor of 0.5 was applied, resulting in a t-test p-value of 0.862. Conclusion(s): PVT-Touch responses correlated very highly to the PVT- 192, though mean and median RT were higher and lapses more frequent. These differences are likely touchscreen-specific. Because values were highly correlated, transformations allowed for direct comparisons. The PVT-Touch has potential to be an easy to use, portable, scalable, inexpensive assessment of sleep loss in the natural environment.