Impacts of Environmental Distractions and Interruptions on Unsupervised Digital Cognitive Assessments in Older Adults: Cognitive Ecological Momentary Assessment Study.

Background: Unsupervised cognitive assessments are becoming commonly used in studies of aging and neurodegenerative diseases. As assessments are completed in everyday environments and without a proctor, there are concerns about how common distractions may impact performance and whether these distractions may differentially impact those experiencing the earliest symptoms of dementia. Objective: We examined the impact of self-reported interruptions, testing location, and social context during testing on remote cognitive assessments in older adults. Methods: Participants from the Ambulatory Research in Cognition smartphone study were classified as cognitively normal (n=380) or as having very mild dementia (n=37). Participants completed daily tests of processing speed, working memory, and associative memory. At each assessment, participants were asked for their current location and social surroundings, which was used to quantify whether participants were either at home (or not) and by themselves (or not). After each assessment session, participants were asked if they experienced any interruptions. Mixed-effect modeling tested the interactions between location, social context, and clinical status. Additional analyses were conducted by removing sessions where participants reported that they were interrupted at any point during the testing period. Results: Across all participants, momentary effects of environmental distractions were minimal. Specifically, when tests were completed in the presence of others, participants exhibited slightly increased variability in processing speed (P=.04). However, these momentary effects of environmental distractions were dependent upon cognitive status (P=.009). Cognitively normal older adults had better visuospatial working memory performance when they completed tests at home compared to when they completed tests away from home (P=.001). However, older adults with very mild dementia showed no effect of testing location on the same task (P=.36). Conversely, cognitively normal older adults did not differ in their processing speed at either testing location (P=.88). Older adults with very mild dementia were slightly faster when not at home (P=.04). Social context only impacted variability in processing speed for participants with very mild dementia (P=.04). When considering tests completed in the most distracting environments (away from home and in the presence of others), those with very mild dementia showed larger differences only on the visuospatial working memory measure. Additional analyses demonstrated that after removing sessions in which participants self-reported experiencing an interruption (1194/9633, 12.4% of all assessments), these small effects of environmental distractions on cognition remained, but were more apparent in those with very mild dementia. Conclusions: Social context and location of unsupervised remote cognitive testing have small impacts on performance, but these impacts were not consistent across cognitive domains and were mostly limited to participants demonstrating the earliest symptoms of dementia. Remote cognitive testing provides valid and reliable data in older adults, but care should be taken to allow participants to report distractions that may occur during testing.