Naturally occurring change in Multiple Sclerosis Walking Scale-12 scores over time in multiple sclerosis.

AIM: This study examined the trajectory and pattern of naturally occurring change in perceived walking impairment over a 30-month period in relapsing-remitting multiple sclerosis (RRMS).

PATIENTS & METHODS: Two hundred and sixty-nine persons with RRMS completed the 12-item Multiple Sclerosis Walking Scale (MSWS-12) every 6 months over a 30-month period. Data were analyzed using latent growth curve modeling and latent class growth curve modeling.

RESULTS: Latent growth curve modeling demonstrated that a linear trajectory adequately described the group-level pattern of change in MSWS-12 scores over time. Latent class growth curve modeling supported a three-class model for describing the heterogeneity of changes in MSWS-12 scores over time.

CONCLUSION: Walking impairment does change over time in RRMS, and this can be described by three patterns of change trajectories that differed based on initial status of walking impairment.