icognition: a smartphone-based cognitive screening battery

Background Telemedicine is feasible and well-accepted by people with multiple sclerosis (MS). Objective The aim of this study is to validate a smartphone-based cognitive screening battery, ico gnition , to faster signal cognitive deterioration. Methods ico gnition consists of three tests (Symbol Test, Dot Test and visual Backwards Digit Span (vBDS)) that are equivalents of validated paper-pencil tests. These are 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 ico gnition , 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 ico gnition correlate well with their paper-pencil equivalent (Symbol Test: r=.63, p<.001; Dot Test: r=.31, p=0.002; vBDS: r=.71, p<.001), negatively correlate with the Expanded Disability Status Scale (EDSS: Symbol Test: rho=-.27, p=.01; Dot Test: rho=-.29, p=.006; vBDS: rho=- .23, p=.027) and show high test-retest reliability (Symbol Test: r=.81, p<.001; Dot Test: r=.75, p<.001; vBDS: r=.84, p<.001). Test performance was not significantly different between people with MS and healthy subjects for all cognitive tests, both in ico gnition and their paper-pencil equivalents. Conclusion ico gnition is a valid and reliable tool to remotely screen for cognitive functioning in persons with MS.