Reliability and validity of the Turkish voice handicap index-partner (VHI-P-TR)

This study examines the Turkish validity, reliability and diagnostic performance of the Voice Handicap Index-Partner (VHI-P-TR), which is used to obtain the perceptions of communication partners of individuals with dysphonia about the functional, physical and emotional handicap resulting from the patient experiencing dysphonia.

The study included 160 individuals with dysphonia and their communication partners. First, translation, back translation, expert validity and pilot study were performed in the scale adaptation process. Then, a confirmatory factor analysis (CFA) was conducted to assess the construct validity of the VHI-P-TR. Correlations between the VHI-P-TR and Voice Handicap Index (VHI-TR) scores of dysphonic individuals were examined to evaluate the concurrent validity of the VHI-P-TR. To assess the reliability of the VHI-P-TR, a test-retest analysis was performed, and internal consistency coefficients (α) were calculated. A receiver operating characteristic (ROC) analysis was conducted to determine the cut-off point for the VHI-P scores.

A high positive correlation was found between the participants' VHI-P-TR and VHI-TR total and subscales mean scores (r's > 0.782; p < 0.01). The VHI-P-TR had high internal consistency regarding for its subscales and total score (α's > 0.94; p < 0.01). Factor loadings of all VHI-P-TR items were higher than 0.30 and their error variances were lower than 0.90. In addition, factor loadings were statistically significant for all the items (p < 0.05). The data fit the model well according to all CFA indices except for GFI (scale = 0.69). An adequate sensitivity and specificity were achieved for the VHI-P-TR, and the cut-off point was found as 11.50 for the total score and ranged from 2.50 to 5.50 for the subscales.

The VHI-P-TR is a valid and reliable measurement tool with high diagnostic performance in all subscales and total score, and has high levels of agreement with the VHI-TR.