Validity of the Community Balance and Mobility Scale in community-dwelling persons after stroke

Objectives: To examine the convergent validity, sensitivity to change, floor and ceiling effects of the Community Balance and Mobility Scale (CB&M) in community-dwelling stroke survivors. The secondary objective was to determine the correlations between the CB&M and lower-limb motor recovery and strength.

Design: Validity study.

Setting: Two university-based research centers.

Participants: Community-dwelling persons after stroke (N=44; 24 men, 20 women; mean age, 62.6+/-12.6y). Baseline measures were taken 3 months after the onset of stroke (98.6+/-52.6d); participants were reassessed 8 months poststroke (246.8+/-57.2d).

Interventions: Not applicable.

Main outcome measures: CB&M, Berg Balance Scale (BBS), Timed Up & Go (TUG), Chedoke McMaster Stroke Assessment (CMSA) Impairment Inventory for leg and foot, concentric bilateral isokinetic strength of the lower-limb flexor and extensor muscle groups using a dynamometer. The magnitude of the associations and the standardized response means (SRMs) among the CB&M, BBS, and TUG were used to examine the convergent validity and sensitivity to change, respectively.

Results: Moderate to high convergent validities (rho=.70 to .83, P<.001) were observed among the CB&M, BBS, and TUG. The CB&M was moderately correlated with the CMSA leg and foot scores (rho=.61 and .63, respectively, P<.001) and the paretic limb strength (rho=.67, P<.001). The CB&M demonstrated the greatest ability to detect change between the baseline and follow-up assessments (SRM=.83).

Conclusions: The CB&M is valid and sensitive to change in assessing functional balance and mobility in ambulatory stroke survivors with moderate to mild neurologic impairments.