JMIR Publications

ABSTRACT

Background:

Cognitive deterioration is prevalent in multiple sclerosis (MS) and requires regular follow-up, which is time-consuming and costly. Telemedicine could offer a solution, as it is feasible and well-accepted by people with MS. Current smartphone-based applications however focus solely on information processing speed, while memory is also commonly affected.

Objective:

To validate a smartphone-based cognitive screening battery, icognition, to signal deterioration in both memory and information processing speed.

Methods:

icognition consists of three tests (Symbol Test, Dot Test and visual Backwards Digit Span (vBDS)). These tests are based on validated paper-pencil tests: the Symbol Digit Modalities Test (SDMT), the 10/36 Spatial Recall Test (SPART) and the auditory Backwards Digit Span (aBDS), respectively. To establish the validity of icognition, 101 people with MS and 82 healthy subjects completed all tests. 21 healthy subjects repeated testing 2 to 3 weeks later.

Results:

All tests in icognition correlate well with their paper-pencil equivalent (Symbol Test: r=.67, P<.001; Dot Test: r=.31, P=.002; vBDS: r=.69, P<.001), negatively correlate with the Expanded Disability Status Scale (EDSS: Symbol Test: rho=-.34, P<.001; Dot Test: rho=-.32, P=.003; vBDS: rho=-.21, P=.04) and show moderate-to-good test-retest reliability (Symbol Test: ICC=.85, r=.85, P<.001; Dot Test: ICC=.73, r=.74, P<.001; vBDS: ICC=.81, r=.83, P<.001). Test performance was comparable between people with MS and healthy subjects for all cognitive tests, both in icognition and the gold standard paper-pencil tests.

Conclusions:

icognition is a valid and reliable tool to remotely screen cognitive performance in persons with MS.