Reliability and Validity of the "Voice Handicap Index (VHI) Adapted to the Singing Voice"

Background: The Voice Handicap Index (i.e., VHI) is one of the most reliable standardized self-evaluation assessments in diagnosis of voice disorders. That tool is the most used in daily clinic. In 2007, the VHI was adapted to the singing population, called VHI adapte aux chanteurs'. The aim of our study was to investigate the reliability and validity of the German version of the VHI adapted to the singing voice. Materials and Methods: 113 German singers (41 males and 72 females) with diverse singing styles and profession were included in the study. They were divided into 2 groups: a test-group (n=20) with self-perceived vocal complaints and a control-group (n=93) without vocal complaints. Statistical analysis to measure the reliability and validity was conducted with the Cronbach's alpha (i.e., Cron. ), independent t-test and receiver operating characteristics as well likelihood ratio, respectively. Results: Reliability was confirmed by acceptable Cron. (0.713-0.850) for each of the sub-scales and total score. The validity between the 2 groups showed high significant differences for each of the sub-scales and total score by which the test-group indicated higher scores than the control-group. Only the construct validity revealed no clear results. Conclusion: The VHI adapted to the singing voice is suited as reliable and valid standardized evaluation tool, but the diagnostic accuracy has to be investigated again because of too high inaccuracy in the interpretation of the outcome of the present data.