Minimum detectable change of the Berg Balance Scale and Dynamic Gait Index in older persons at risk for falling.

BACKGROUND

The Berg Balance Scale (BBS) and the Dynamic Gait Index (DGI) are often the central components of the physical therapy evaluation to identify older adults at risk of falling.

PURPOSE: The purpose of this study was to use the standard error of measurement to investigate the minimal detectable change associated with these clinical instruments.

METHODS

A sample of 42 community dwellers (older than 65 years) with a history of falls or near falls was evaluated with the BBS and DGI. Evaluations were videotaped and later rescored by 2 experienced physical therapists.

RESULTS

The mean initial BBS was 39 points (SD = 8.9, range 17-53). Rescored mean value was 40 points (SD = 8.8, range 19-55). The DGI mean initial value was 12.9 (SD = 4.5, range 3-21), and the rescored mean was 12.7 (SD = 4.6, range 4-22). MDC95% values were 6.5 BBS and 2.9 DGI points, respectively.

CONCLUSION

These results suggest that a change of 6.5 point in the BBS and 2.9 points in the DGI is necessary to be 95% confident that genuine change in function has occurred between 2 assessments. This information is important for assessing and monitoring progress and guiding treatment for community dwellers at high risk of falling.