JMIR Publications

ABSTRACT

Background:

Clinical trials in neurological and psychiatric indications are hampered by poor measurement fidelity in currently used “standardized” rating scales. Digital, repeatable tests that can be remotely administered provide a more fine-grained understanding of the patient’s clinical trajectory. Several such tools are being developed, but few have been validated with respect to discerning and describing change-over-time, which is a critical element of clinical trials.

Objective:

Four cognitive tasks from a digital battery (delivered via tablet) are here administered at high frequency following alcohol challenge to assess sensitivity to change. Tasks are novel, repeatable and self-administered implementations of classic neurobehavioral paradigms.

Methods:

30 healthy younger adults were assessed on two days, under the influence of alcohol or placebo (order counterbalanced), with 8 assessments per day. Tasks included novel, engaging implementations of: Digit-Symbol Substitution Task (DSST); Reaction time; N-back working memory; and visual associative/episodic memory, compared to benchmark measures. In-lab assessment was preceded by massed practice (3 sessions) and blood alcohol concentration was measured throughout using breathalyzer and visual analogue scale.

Results:

Impairment due to alcohol was observed on multiple measures, followed by return to baseline as blood alcohol concentration fell. There was a slight practice effect between first and second session for digital DSST and a longer-term effect across the two days. Strong-to-moderate correlations between digital and benchmark measures were observed at peak intoxication.

Conclusions:

Under alcohol challenge, this battery, along with benchmark standardized tests, is sensitive to subtle changes in cognitive performance over time. Practice effects are minimal in this condensed protocol. Patient-friendly, repeatable tests administered via a digital platform, like those in the current battery, deserve further interrogation in the context of remote clinical studies requiring methodologic approaches for discerning and describing small changes over time. Availability of validated single tests/batteries of tests as sensitive tools that could be frequently administered with ease (e.g. daily), would fill the current gap for availability of descriptors with the requisite sensitivity, specificity and reliability to detect cognitive changes-over-time in clinical trials of new therapies in neurology and psychiatry.