Cross-cultural adaptation and reliability analysis of the Brazilian version of Pediatric Balance Scale (PBS)

Background: The Pediatric Balance Scale (PBS) was developed from a modified version of the Berg Balance Scale aiming to obtain a balance scale more appropriate for the child population. Objectives: To adapt the PBS into Brazilian-Portuguese and to evaluate the intra and inter-rater reliability of the Brazilian-Portuguese version of PBS. Methods: To perform the cross-cultural adaptation of the American version of PBS four translators were involved, who have performed two translations and their respective back-translations. Then, a review by a multidisciplinary committee and a subsequent an assessment of the equivalence of meaning between the back-translations and the original English scale were performed by 3 and 30 healthcare professionals respectively. The intra-rater reliability of the final version of the Brazilian-Portuguese PBS was evaluated using a test-retest design with one-week interval. The Brazilian-Portuguese version of the PBS was tested twice on the same day by two different raters to test the inter-rater reliability. The inter-rater reliability, which was measured from a video of the volunteers performance, was evaluated by comparing the score given by five raters independently. Reliability was evaluated by Intraclass Correlation Coefficient (ICC). Fifteen volunteers (11 +/- 2.7 years) diagnosed with Cerebral Palsy (CP) classified at level I and II on the Gross Motor Function Classification System (GMFCS) were assessed. Results: The reliability of the PBS total score for both intra-rater (ICC=0.85) and inter-rater (ICC=0.91) was excellent. The inter-rater reliability (measured from the video) for the total score was also classified as excellent (ICC=0.98). Conclusion: The results showed adequate reliability for the PBS for pediatric population with CP diagnostic classified at level I and II on the GMFCS.