Study on the simplified Chinese version of the voice handicap index

To investigate the characteristics of the simplified Chinese versions of the Voice Handicap Index (VHI).

Cluster analysis was performed on the VHI scores of 1766 dysphonic patients to screen for items to compile different simplified Chinese VHI versions. The VHI scores of 3825 dysphonic patients (in which 424 patients have undertaken surgical treatment) and 120 control subjects were assessed using the simplified versions, and the results were compared between the simplified versions and the original version.

Two simplified versions of VHI-10 (10 items) and VHI-13 (13 items) were compiled after the cluster analysis. Their internal consistency reliabilities were 0.939 and 0.936, the test-retest reliability coefficients were 0.995 and 0.993, and their correlation coefficients to the original VHI questionnaire were 0.972 and 0.973, respectively. The scores of VHI-10 and VHI-13 were significantly higher in dysphonic patients than in control subjects (Z=17.42, Z=17.46; P=0.000). The mean ratios of the VHI-10 and VHI-13 scores to the original VHI questionnaire scores in dysphonic groups were found to be consistently greater than expected (0.333 and 0.433, respectively). The VHI scores from the simplified versions were classified on the basis of the overall grade severity of dysphonia according to the physicians' subjective auditory assessment, and when the scores among the different groups were compared, there was a statistical difference between the VHI-10 and VHI-13 scores (Z=5.735-9.861, P=0.000). The VHI-10 and VHI-13 patient scores declined significantly after treatment (P<0.05).

Both of the simplified Chinese versions, VHI-10 and VHI-13, had good reliability and validity. They could be used in the dysphonic self-assessment as the simplified Chinese VHI questionnaire. VHI-10 was found to be more concise and more widely applicable than VHI-13.