Xavier Montalban, M.D., Ph.D., from the Hospital Universitari Vall d’Hebron in Barcelona, Spain, and colleagues assessed performance characteristics of the Floodlight Proof-of-Concept study app in a 24-week study involving 76 people with MS and 25 healthy controls. Smartphone-based active tests and passive monitoring assessed cognition, upper-extremity function, and gait and balance. Test-retest reliability and correlations with clinical and magnetic resonance imaging outcome measures were examined using intraclass correlation coefficients (ICCs) and age- or sex-adjusted Spearman’s rank correlation.

The researchers found that across tests, ICCs were moderate to good in persons with MS. For all tests in the cognitive, upper-extremity function, and gait and balance domains, except for the Static Balance Test, the correlations with domain-specific standard clinical disability measures were significant. There were correlations observed for most tests with the Expanded Disability Status Scale, 29-item Multiple Sclerosis Impact Scale items or subscales, and/or normalized brain volume.

“The higher temporal resolution and multidimensional feature space of functional data collected by this platform hold the potential to capture subtle, potentially disease-related information which are not readily discriminated by clinician-administered assessments,” the authors write.

Several authors disclosed financial ties to biopharmaceutical companies, including F. Hoffmann-La Roche, which provided study funding.