Table 2.

Adherence rates by study activity.

	Full study period
Study app surveys, n	286a
Daily surveyb, %	69.18
Weekly surveys, %	68.37
Biweekly surveys, %	72.86
Monthly surveys, %	68.82
ResearchKit tasks, nc	164
Cognitive active tasks, %	80.59
Cambridge cognition, nd	289
Cognition tasks, %	56.49
ESe check-ins, n	297
Biweekly check-insf, %	75.62
Oura Smart Ring, ng	296
Oura Ring use, %	90.60
On-shift wearable subarm, n	95
Garmin Smartwatch use, %	90.42

^aExcluding 11 participants who were Android users and unable to use the study app.

^bAll study app survey completion calculations exclude 12 participants (11 retained) with Android sensors who have no study app data

^cResearchKit active tasks were switched to Cambridge Cognition tasks on July 6, 2020; therefore, some participants did not receive at least 1 ResearchKit tasks as reflected by a smaller study sample size

^dThe higher sample size reflects a few Android users who were able to access the web-based Cambridge Cognition links.

^eES: engagement specialist.

^fOf the 297 retained participants, 2 completed 0 check-ins.

^gOne retained participant never synced their ring to the app.