Is the Brief-BESTest Brief Enough? Suggested Modifications Based on Structural Validity and Internal Consistency.

BACKGROUND

The Brief Balance Evaluation Systems Test (Brief-BESTest) could be a useful tool for balance assessment. Although some psychometric characteristics have been examined, others still need to be clarified.

OBJECTIVE

The objective was to assess the structural validity, convergent validity, discriminant validity, and internal consistency of the Brief-BESTest in neurological patients.

DESIGN

This was a cross-sectional study.

METHODS

Data were from 416 patients with neurological disease and related balance disorders. Patients were assessed with the 5-levels Activities-Specific Balance Confidence Scale (ABC 5-levels), Brief-BESTest, and some simple balance tests (ie, 1-leg stance, Timed "Up & Go" test, functional reach, and a fall history questionnaire). Three Brief-BESTest models were examined through confirmatory factor analysis, and the following indexes were calculated: Comparative Fit Index, Tucker-Lewis Index, and root-mean-square error of approximation. Convergent validity was assessed by calculating the correlation between Brief-BESTest and ABC 5-levels total scores. Receiver operating characteristics assessed the ability of each model to differentiate between people with falls and those without falls. Internal consistency was measured with Cronbach α and coefficient ω.

RESULTS

Confirmatory factor analysis showed model 3 (Comparative Fit Index = 0.97; Tucker-Lewis Index = 0.95; root-mean-square error of approximation = 0.05), with item 1 removed and error covariance between items 3 and 4 and between items 5 and 6, to have a significantly better structure than models 1 and 2. The correlation between Brief-BESTest and ABC 5-levels was 0.61 (Spearman ρ) for all 3 models. The area under the curve of the receiver operating characteristics showed an acceptable accuracy (0.72) in distinguishing patients with a history of falls from those without a history of falls (95% confidence interval = 0.66-0.78) for all models and was superior to the areas under the curve of other simple balance tests (1-leg stance, Timed "Up & Go" test, functional reach). Cronbach α was good for Brief-BESTest models 1 (0.92) and 3 (0.92), but ω was greater than 0.80 only for model 3.

LIMITATIONS

The sample was heterogeneous.

CONCLUSIONS

The Brief-BESTest, after some changes, shows good validity and internal consistency in patients affected by different balance disorders.