Introduction: Cognitive impairment is frequent in persons with multiple sclerosis (PwMS) and can impact on activities of daily living. The capacity to differentiate real changes from background statistical noise induced by human, instrumentational, and environmental variations inherent to the evaluation would improve cognitive assessments. Objective: To assess the short-term reproducibility of cognitive tests in non-multiple sclerosis (non-MS) persons and PwMS. Methods: Sixty-two PwMS and 19 non-MS persons performed 2 measurements, 1 week apart, of the Symbol Digit Modalities Test (SDMT) and phonological and semantic verbal fluency. Test-retest reliability was evaluated by the intraclass correlation coefficients (ICC) and agreement by standard error of measurement (SEM) and minimum detectable change (MDC). Results: The reliability of the cognitive variables studied had moderate to high ICC values (ICC > 0.8) in both populations. The threshold to consider a significant cognitive modification evaluated by SEM and MDC was lower in PwMS compared with non-MS persons. Conclusions: SDMT and verbal fluency have good short-term reproducibility in PwMS. Specific SEM and MDC cutoffs based on the same design of evaluation (especially retest timing) and to the targeted pathological population (MS vs. healthy) should systematically be used to consider cognitive modification as significant in research protocol as well as in clinical practice.

Background: Walking disorders represent the most disabling condition in persons with Multiple Sclerosis (PwMS). Several studies showed good reliability of the 6-min walk test (6MWT) (i.e., especially distance traveled), but little is known about the reliability of the Spatio-temporal (ST) variables in the 6MWT. Objective: To evaluate the test-retest reliability of ST variables and perceived exertion during the 6MWT in PwMS and comparable healthy persons. Methods: We explored three 1-min intervals (initial: 0′–1′, middle: 2′30″–3′30″, end: 5′–6′) of the 6MWT. Six ST variables and perceived exertion were measured (respectively, using the GAITRite system and the Borg Scale). These measurements were performed twice, 1 week apart. The test-retest effects were assessed using the intraclass correlation coefficient (ICC) or the weighted kappa. Results: Forty-five PwMS and 24 healthy persons were included. The test-retest reliability of ST variables values was good-to-excellent for PwMS (ICC range: 0.858–0.919) and moderate-to-excellent for healthy persons (ICC range: 0.569–0.946). The test-retest reliability values of perceived exertion were fair for PwMS (weighted kappa range: 0.279–0.376) and substantial for healthy persons (weighted kappa range: 0.734–0.788). Conclusion: The measurement of ST variables during these 6MWT intervals is reliable and applicable in clinical practice and research to adapt rehabilitation care in PwMS.

The assessment of the functional performance status of persons with multiple sclerosis (PwMS) is a useful tool to optimize healthcare. This concept does not seem to be extensively explored in this population. This study aimed to determine the level of activity of PwMS during weekdays and weekends, and to establish associations between clinical parameters. Forty-one PwMS and 16 healthy persons participated in this study. Their physical activity in real-life conditions was assessed with an accelerometer. For the clinical evaluations, the quality of life, fatigue, gait, and balance were assessed. The level of activity between PwMS for weekdays, weekends, Saturdays, and Sundays was significantly reduced compared with the reference group (p = 0.001–0.00001, d = 0.95–1.76). PwMS had a constant level of activity throughout the week, whereas the reference group increased its level of activity on Saturdays (p = 0.04, d = 0.69). The level of activity was correlated in descending order with multiple sclerosis disability, body mass index, gait velocity, six-minute walk test, and timed up and go test. This study showed that PwMS had a stable level of activity throughout the week, contrary to healthy persons. It could be necessary to develop programs to facilitate physical activity and participation during the weekdays, but especially during weekends.