Interobserver reproducibility of the Berg Balance Scale by novice and experienced physiotherapists

This study aimed to assess the interobserver reliability of the Brazilian-Portuguese version of the Berg Balance Scale (BBS), which consists of 14 items that evaluate body balance during daily activities. The assessment was made by physiotherapists with extensive or little clinical experience in noninstitutionalized elderly individuals. Participants comprised 12 elderly subjects (10 women and 2 men) with mean ages of 75.8+/-8.4 years (range=63-87) and 18 physiotherapists with varying clinical experience. Interexaminer reliability obtained for each scale item yielded weighted kappa value >0.75 in 11 of the 14 items (varying from 0.37 to 1.0). The intraclass correlation coefficient (ICC) for the total sum of BBS scores between the two groups of physiotherapists was 0.996 (95% confidence interval, 0.987-0.999) with a Cronbach alpha coefficient of 0.996. We found no statistically significant difference between the rater groups when we compared the sum score means obtained with Student's t-test (p=0.86). Although some items had low reliability values, in general our results suggest that the Brazilian-Portuguese version of the BBS showed acceptable levels of interrater reliability and agreement when used by physiotherapists with different clinical practice levels and without previous training on noninstitutionalized elderly patients.