Cross cultural adaptation of Berg balance scale in Greek for various balance impairments

Abstract

Rationale, Aim & Objectives: The Berg Balance Scale (BBS) although widely used for assessing balance, it has not been officially adapted into Greek. The aim therefore, of this research is to translate and validate the cross cultural adaptation of the Greek BBS (BBS-GR). Method: The BBS-GR was adapted according to international guidelines, (forward & backward translation, by four bilingual independent translators). The pre-final BBS-GR was piloted by 6 physiotherapists (1-5 years of experience) and 12 patients (5 men & 7 women, age 76±7 years) in the 1st pilot study and by 10 patients (7 men & 3 women, age 57±20 years) during the 2nd pilot study with balance impairments. After modifications, the final BBS-GR was undertaken to 112 patients (43 men, 69 women, age 67±19 years) for its psychometric testing. It was administered by two raters, twice over a 10 day period, to assess both inter- and test-retest reliability correspondingly. Bland-Altman analysis presented the levels of agreement between measurements. Validity was assessed by correlation of the BBS-GR with the Greek mini-Balance Evaluation Systems Test (mini-BESTest), the Functional Reach Test (FRT), the Timed Up and Go test (TUG) and the questionnaire of Falls Efficacy Scale-International (FES-I). Results: Minor modifications to one item were required for the final BBS-GR version, and showed: excellent inter-rater reliability (ICC=0.998), test-retest (ICC=0.976) reliability and internal consistency (Cronbach's alpha=0.830). Measurements showed a level of agreement (meandif=0.126±0.7, p>0.05). Spearman’s correlations coefficient (rs) were strong between the BBS-GR and the Greek mini-BESTest (rs=0.844, p<0.001), the TUG (rs=-0.781, p<0.001), the FRT (rs=0.650, p<0.001) and FES-I (rs=-0.501, p<0.001), indicating good validity properties. Responsiveness across fallers and non fallers showed a moderate effect size (0.54). Conclusion: The excellent psychometric characteristics of the Greek BBS highly recommend its utility to the Greek clinical setting. Further research should be undertaken to evaluate responsiveness over treatment conditions.