Abstract
OBJECTIVES: After confirming the measurement properties of the Berg Balance Scale (BBS) in patients with stroke by conducting a Rasch analysis, this study sought: (i) to generate a keyform as a tool for goal-setting and intervention-planning; and (ii) to determine the appropriate strata for separating patients' postural balance ability. DESIGN: Methodological analyses of cross-sectional study data. PATIENTS: A pooled sample of 156 patients with stroke: mean (standard deviation) age 74.4 (12.9) years. METHODS: This study evaluated the BBS's rating scale structure, unidimensionality, and measurement accuracy (0: unable to perform or requiring help, to 4: normal performance) and then generated a keyform and strata. RESULTS: The BBS rating scale fulfilled the category functioning criteria. Principal component analysis of standardized residuals confirmed the unidimensionality of the test. All items fit the Rasch analysis. Person ability-item difficulty matching was good. Person reliability was 0.96, and the patients were divided into 9 strata. The keyform for the BBS will enable clinicians and investigators to estimate patients' postural balance ability and monitor their progress. CONCLUSION: The BBS has strong measurement properties. This study generated both a keyform that can contribute to clinicians' decision-making in goalsetting and intervention-planning and strata that can facilitate understanding of patients' abilities.