Assessing functional status: exploring the relationship between the multiple sclerosis functional composite and driving.

OBJECTIVE To explore the relationship between the Multiple Sclerosis Functional Composite (MSFC), which is comprised of 3 clinical dimensions (arm and hand function, leg function and ambulation, cognition), and an everyday functional skill, driving performance. DESIGN Cohort study. SETTING Medical rehabilitation research organization. PARTICIPANTS Twenty-nine individuals with documented multiple sclerosis (MS) and limited motor decrements. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Driving-related skills were measured by using the overall category rating from the Useful Field of View (UFOV) Test, its 3 subtests, the error and latency scores from the Neurocognitive Driving Test (NDT), subjective (self-report) and objective (Department of Motor Vehicles [DMV] reports) reported driving experience, and number of motor vehicle crashes. Within the group, differences were explored between participants rated as low risk versus moderate-high risk on the UFOV overall score and between participants who reported a change in driving habits after MS versus those who reported no change. RESULTS The overall MSFC score correlated significantly with the UFOV overall score, the visual-information processing and selective attention subtests of the UFOV, the NDT latency score, as well as with the number of days a week the individual drove and the number of crashes reported by the DMV. An examination of the MSFC components revealed that the cognition component was significantly related to the UFOV overall score, all 3 subtests of the UFOV, and the NDT latency score. The arm and hand function component correlated significantly with NDT latency and the selective attention subtest of the UFOV. Individuals classified as low risk on the UFOV overall had more education, better MSFC scores, and lower NDT latency scores. Only the overall MSFC score distinguished those who reported a change in driving habits after onset of MS. CONCLUSIONS Problems with everyday functional skills such as driving are accurately identified through the use of the overall MSFC and its components.