Cross-Cultural Adaptation and Validation of the Mandarin Chinese Version of the Vocal Performance Questionnaire

Objective: The Mandarin Chinese version of the Vocal Performance Questionnaire (VPQ-CM) for evaluating vocal performance. Methods: A total of 120 participants with vocal disorders and 120 healthy participants completed this study. Investigators translated the original VPQ into the VPQ-CM, and participants completed the questionnaire fill it. Investigators assessed the reliability by internal consistency and test-retest. And investigators evaluated content validity through expert consensus by the Delphi method, measured structural validity by factor analysis, and assessed criterion validity by analyzing the correlation between VPQ-CM and Voice Handicap Index-10 (VHI-10). Discriminant validity was evaluated by comparing the scores of participants with vocal disorders and healthy participants for significant differences. Receiver Operating Characteristic curve analysis was utilized to identify the cutoff score to distinguish participants with or without vocal disorders. Results: VPQ-CM demonstrated internal consistency (Cronbach's α = 0.882) and test-retest reliability (intra-class correlation coefficient: 0.954). The expert committee unanimously agreed that the questionnaire had good content validity (expert authority level Cr = 0.767-0.967, coefficient of variation Cv = 5.23%-16.64%). The loading values of each item in the described common factors of the VPQ-CM were greater than 0.4, indicating good structural validity. There was a significant correlation between the VPQ-CM and VHI-10 (r = 0.608-0.761, P < 0.001), demonstrating good criterion validity of the questionnaire. Significant differences were observed in the VPQ-CM scores between participants with and without vocal disorders (P < 0.001), indicating good discriminant validity of the VPQ-CM. Conclusion: The VPQ-CM demonstrated good reliability and validity and can be utilized for clinical measurement of vocal performance in patients with vocal disorders.