Singing Voice Handicap Index-12 : Development and validation of aGerman version

Abstract

The aim of this study was to develop ashortened German version of the Singing Voice Handicap Index (SVHI). The SVHI is aone-dimensional instrument for self-assessment of avoice disorder in singers. The questionnaire developed in the USA comprises 36items and has been available in avalidated German version since 2013. Bicentric data from atotal of 200 patients formed the basis for item analysis and selection. Using corrected item-total correlations, 12items were selected for the abridged version. The internal consistency was calculated. The SVHI-12 was subsequently validated in 97vocal patients and 105 vocally healthy singers (control group) using the test-retest procedure. The SVHI-12 achieved agood internal consistency (Cronbach's alpha = 0.93) and agood test-retest reliability (intra-class correlation r = 0.88 ; p < 0.001). The patients had significantly higher overall scores (18 ± 13 vs. 7 ± 6) compared to the healthy control group. The SVHI-12 overall score correlated significantly positively with the severity of the voice disorder as reported by the patient (r = 0.68; p < 0.001). As athreshold value above which avoice can be described as disturbed, atotal score > 7points was calculated using receiver operating curve analysis. As an indication of avoice disorder, asensitivity of 81% and aspecificity of 71% is thus achieved (Youden index 0.523, area under the curve 0.827, 95% confidence interval 0.769-0.885). The shortened SVHI has similarly good psychometric characteristics to the original SVHI. With the SVHI-12, avalid and effective instrument for the detection of singing voice disorders is available for German-speaking countries.