Reliability and Validity of the Persian version of the Rivermead Mobility Scale in multiple sclerosis patients

Using Rivermead Mobility Scale (RMI) is common to evaluate the mobility in neurological patients. Since, a Persian version of RMI is not still available, this study was designed to develop Persian-RMI version and evaluate its reliability and validity for mobility assessment in patients with multiple sclerosis. Forty three MS patients completed Persian version of RMI and Fatigue Severity Scale (FSS) in two different sessions with 2 weeks interval. In addition, they completed three functional tests included; a) Timed Get-Up and Go Test (TGUGT), b) Timed 25 Foot Walk Test (T25FWT), and Two-minute Walk Test (2MWT) in the first session. The coefficient of reproducibility of Persian-RMI was ranged from 0.716 to 0.951 for each of items between two sessions and 0.877 for total. The item to total correlation coefficients ranged from 0.426 to 0.903 (P<0.005). Persian-RMI showed a good to excellent correlation with FSS (first session, r = -0.734; second session r = -0.746), T25FWT (r = 0.806), TGUGT (r = -0.851) and 2MWT (r = 0.795). The results confirm internal consistency and construct validity of the Persian-RMI to evaluate mobility index in Iranian patients with multiple sclerosis. However, more study is needed to investigate its validity to evaluate the mobility in other neurological patients in populations with Persian language.