Activities-specific Balance Confidence (ABC) Scale adapted for the mainland population of China

Objective: To evaluate the reliability and validity of a Chinese Mandarin version of the Activities-specific Balance Confidence (ABC) Scale. Design: Cross-sectional. Setting: A rehabilitation centre for adults. Participants: Sixty-one elderly people living in the community. Main outcome measure: Self-efficacy in balancing ability was assessed via a Mandarin Chinese version of the ABC Scale. Results: The intraclass correlation coefficients for test-retest and inter-rater reliability of the Chinese Mandarin version of the ABC Scale were 0.98 (95% confidence interval (CI) 0.96-0.99) and 0.96 (95% CI 0.94-0.98), respectively. The Cronbach's alpha coefficient of internal consistency was 0.94. In the Bland-Altman analysis the mean difference in the ABC test-retest scores was -1.81, and the 95% limits of agreement varied from -10.67 to 7.03. The evaluation of inter-rater reliability showed that the mean difference was -1.13, and the 95% limits of agreement varied from -9.55 to 7.30. The factor analysis method was adopted to assess the validity of the scaled activities and two factors contributed to total variance at 52.5% and 13.6%, respectively. Conclusion: The Chinese Mandarin version of the ABC Scale is reliable and valid, and is suitable for assessments of balance confidence in aged people in mainland China.