Over the past six decades, polysomnography, actigraphy, and most recently smartphone technology have created a trifecta of options for measuring sleep. It remains to be seen whether smartphone applications are comparable to actigraphy in objectively monitoring sleep. The present study had 29 healthy adult participants fill out a sleep diary and use the Sleep Time app (Azumio, Inc.) to monitor their sleep for one week. A subset of 19 participants also wore an actigraphy bracelet. Self-report questionnaires characterized sleep habits and psychological profiles of participants, while cognitive assessments were implemented to examine potential correlations between total sleep time (TST) and/or sleep efficiency and executive functioning. The smartphone app overestimated TST when compared to actigraphy, yielding a significant difference, t(18) = -6.64, p = .01, r2 = .71. Moreover, a statistical trend indicated that the app also overestimated sleep efficiency, t(18) = -2.06, p = .06, r2 = .12 There were no correlations between self-reported sleep quality and performance on cognitive tasks or total number of caffeinated beverages consumed in this sample. Overall, results show that this smartphone app is not accurate in monitoring TST or sleep efficiency when compared to actigraphy. Future research is needed to investigate the utility of smartphone applications in monitoring sleep in clinical populations and across other smartphone apps and phone models
