The subjective minimal important change for the Six Spot Step Test in people with multiple sclerosis - The Danish MS Hospitals Rehabilitation study

Introduction The Six Spot Step Test has shown good psychometric properties in terms of validity and reliability in people with multiple sclerosis. Yet, the responsiveness and minimal important change are unknown. The objective was to investigate the responsiveness of the Six Spot Step Test against the perceived change of walking limitations and establish estimates for the minimal important change in people with multiple sclerosis. Methods The Six Spot Step Test was performed before and after four weeks of specialised multidisciplinary inpatient rehabilitation by 142 adults with mild to severe multiple sclerosis. Responsiveness was determined based on anchor- and distribution-based methods, using the Multiple Sclerosis Walking Scale-12 as external criterion. In a supplementary analysis, the Six-Minute Walking Test was used as an external criterion. Results The correlation between the baseline ( r = 0.56, p