A prospective study to establish the minimal clinically important difference of the Mini-BESTest in individuals with stroke

Objective: To determine the minimal clinically important difference of the Mini-BESTest in individuals' post-stroke. Design: Prospective cohort study. Setting: Outpatient stroke rehabilitation. Subjects: Fifty outpatients with stroke with a mean (SD) age of 60.8 (9.4). Intervention: Outpatients with stroke were assessed with the Mini-BESTest before and after a course of conventional rehabilitation. Rehabilitation sessions occurred one to two times/week for one hour and treatment duration was 1.3-42 weeks (mean (SD) = 17.4(10.6)). Main measures: We used a combination of anchor- and distribution-based approaches including a global rating of change in balance scale completed by physiotherapists and patients, the minimal detectable change with 95% confidence, and the optimal cut-point from receiver operating characteristic curves. Results: The average (SD) Mini-BESTest score at admission was 18.2 (6.5) and 22.4 (5.2) at discharge (effect size: 0.7) (P = 0.001). Mean change scores on the Mini-BESTest for patient and physiotherapist ratings of small change were 4.2 and 4.3 points, and 4.7 and 5.3 points for substantial change, respectively. The minimal detectable change with 95% confidence for the Mini-BESTest was 3.2 points. The minimally clinical importance difference was determined to be 4 points for detecting small changes and 5 points for detecting substantial changes. Conclusions: A change of 4-5 points on the Mini-BEST is required to be perceptible to clinicians and patients, and beyond measurement error. These values can be used to interpret changes in balance in stroke rehabilitation research and practice.