VHI-10 and SVHI-10 Differences in Singers' Self-perception of Dysphonia Severity

Summary

Objective

Previous investigations of the Voice Handicap Index (VHI)-10 in clinical practice noted that specific information relevant to singers was not forthcoming. Consequently, a second index, the Singing Voice Handicap Index (SVHI) as well as its shortened counterpart the SVHI-10, was developed. The purpose of this study was to directly compare the differences in scores between the VHI-10 and the SVHI-10 in a group of 50 singers.

Methods

A retrospective chart review of 50 singers (26 women, 24 men) was performed between June 2014 and November 2014 at Weill Cornell Medical College, New York. Subjects completed both the VHI-10 and the SVHI-10 at their initial evaluation. The results from the VHI-10 and the SVHI-10 were then compared using paired t test and two-way analysis of variance.

Results

The SVHI-10 scores from the performers were significantly higher than those of the VHI-10 (P < 0.0001). The mean score on the VHI-10 was 12.1 compared with 20.4 on the SVHI-10 (maximum score for each questionnaire is 40). There were no significant gender differences when comparing the VHI-10 and the SVHI-10 on the overall scores or for individual items. The analysis of variance also found no significant gender difference (P = 0.865) and confirmed a significant difference between VHI-10 and SVHI-10 (P = 0.0003).

Conclusion

Whereas singers may have general complaints about their voice, they also have specific complaints that relate only to their singing voice. Finding a significant difference between the scores of the VHI-10 and the SVHI-10 suggests the importance of assessing the singer's perception of voice severity using a tool that focuses on the singing voice.

Introduction

Objective analysis of therapeutic results in the management of voice disorders has been a challenge.¹ Consequently, outcomes research has been the mainstay for determining the need for clinical management of voice disorders and for voice research. Outcomes research places the focus of the impact of disease and subsequent treatment on the patients' subjective evaluation of their voice disorder as well as the clinician's impression of changes. In 1997, Jacobson et al published the Voice Handicap Index (VHI), a 30-item series of statements about the use of the voice, which is scored from zero (never) to 4 (always).² The VHI was later shortened and validated to the VHI-10, a 10-item form now used by clinicians around the world.³

During the development of the VHI and the VHI-10, the statements that compose the indexes were organized into three categories—functional, physical, and emotional. The VHI comprises 10 functional items, 10 physical items, and 10 emotional items. From those 30 items, the VHI-10 was reduced to five functional items, three physical items, and two emotional items.

As the VHI-10 was used in clinical practice, differences were noted between nonsinger and singer populations. VHI-10 lacked statements specifically about singers and the singing voice. Several investigators identified differences between singers and nonsingers in their use of the VHI-10. Phyland et al compared 167 vocal performers with 86 nonperformers and found that the vocal performers were more likely to be diagnosed with a vocal condition in the past 12 months (44% compared with 21%) and were more likely to suffer vocal disability (69% compared with 41%).⁴ Despite these significant complaints regarding their voice, Rosen and Murry found that, when compared with nonsingers, singers scored significantly lower on the VHI (less severe).⁵ To explain this paradoxical finding, Murry et al compared the VHI-10 responses of 35 singers with that of 35 nonsingers. They found that the two groups ranked differently the 10 statements that compose the VHI-10. In addition, when Murry et al changed three statements to “my singing voice,” rather than simply “my voice,” the singers judged their voice complaints as more severe.⁶

The above findings led to the development of a second index, the Singing Voice Handicap Index (SVHI)⁷ and its shortened counterpart the SVHI-10,⁸ which were developed and validated on performers. To develop the SVHI, a clinical consensus conference (comprising laryngologists and speech pathologists) generated an 81-item list of voice complaints that they felt would be of particular concern to singers. This list was then narrowed to 36 items and then administered by Cohen et al to a group of 112 singers with dysphonia and 129 singers with normal voice. They found a high test-retest reliability, as well as a high internal consistency.7, 8

In an effort to simplify the more cumbersome 36-item SVHI, Cohen et al undertook the development of the SVHI-10.⁸ Once again, a clinical consensus conference selected 16 items (from the original 36), which in their combined opinion had the highest content validity. Ultimately, 10 of the highest items in content validity were retained to create the SVHI-10. This shortened survey was then administered to a group of 91 singers with dysphonia at their initial evaluation. A second survey was mailed to them 1 day later. Once again, there was a high test-retest reliability, as well as a high internal consistency.

The SVHI and the SVHI-10 were developed differently from the VHI and the VHI-10. No attempt was made to identify an equal number of items related to physical, functional, and emotional parameters in the SVHI or the SVHI-10. Nonetheless, by examining the statements, the current authors categorized the 10 statements into the broad categories of physical, functional, and emotional (Table 1).

Presently, there are no data that directly compare responses of a large group of singers on both self-assessment tools. The purpose of this study was twofold. First, to directly compare the scores from the VHI-10 and the SVHI-10 in a group of 50 singers and to examine the relative importance of each item as it relates to singers' perception of voice severity. Second, to use the same analysis to explore differences between male and female singers.