Validating virtual administration of neuropsychological testing in Parkinson disease: a pilot study.

Background COVID-19 has highlighted the need for remote cognitive testing. Virtual testing may lessen burden and can reach a larger patient population. The reliability and validity of virtual cognitive testing in Parkinson disease (PD) is unknown. Objectives To validate neuropsychological tests for virtual administration in PD. Methods Participants enrolled in an observational, cognition-focused study completed a rater-administered cognitive battery in-person and via video conference 3-7 days apart. Order of administration was counterbalanced. Analyses to compare performance by type of administration (virtual versus in-person) included paired t-test, intraclass correlation (ICC) and linear mixed-effects models. Results Data for 35 (62.9% male) PD participants (62.5% normal cognition, 37.5% cognitive impairment) were analyzed. Only the semantic verbal fluency test demonstrated a difference in score by administration type, with a significantly better score when administered virtually (paired t-test p = 0.011 and linear mixed-effects model p = 0.012). Only the Dementia Rating Scale-2, Trails A test and phonemic verbal fluency demonstrated good reliability (ICC value 0.75-0.90) for virtual versus in-person administration, and values for visit 1 versus visit 2 were similarly low overall. Trail making tests were successfully administered virtually to only 18 (51.4%) participants due to technical issues. Conclusions Virtual cognitive testing overall is feasible in PD, and virtual and in-person cognitive testing generate similar scores at the group level, but reliability is poor or moderate for most tests. Given that mode of test administration, learning effects and technical difficulties explained relatively little of the low test-retest reliability observed, there may be significant short-term variability in cognitive performance in PD in general, which has important implications for clinical care and research.