Reliability, Measurement Error, and Responsiveness of the Voice Handicap Index: A Systematic Review and Meta-analysis.

OBJECTIVE

To analyze the reliability, measurement error, and responsiveness of the Voice Handicap Index (VHI) for measuring voice handicap in individuals with voice disorders.

METHODS

This systematic review followed the recommendations of the COnsensus-based Standards for the Selection of Health Measurement INstruments. Studies that validated the VHI, analyzed the measurement properties of reliability, measurement error, or responsiveness, and had dysphonic individuals as the study population were included. The following electronic databases were searched: Cochrane Library, EMBASE, LILACS, PubMed, Scopus, and Web of Science. The manual search was carried out on gray literature in the Biblioteca Digital Brasileira de Teses e Dissertações and ProQuest Dissertation & Theses, in addition to mapping citations and consulting an expert in the field. Evidence selection, data extraction, risk of bias analysis, certainty of evidence, and good psychometric measurements were performed by two blinded and independent reviewers. A meta-analysis was performed using Fisher's transformed r-to-z correlation coefficient and standardized mean difference. Heterogeneity was calculated using Tau² and I² statistical tests in JAMOVI 2.3.2 software.

RESULTS

Eighty studies were included in the meta-analysis. When assessing the risk of bias, most studies were classified as inadequate during the reliability and measurement error stages. In the responsiveness stage, they were classified as doubtful in the sensitivity and specificity sub-boxes and good in the comparison sub-box with a gold standard instrument. For psychometric properties, most studies were classified as indeterminate in terms of both reliability and responsiveness. In test-retest reliability and responsiveness, the average outcome differed significantly from zero, indicating agreement between the test and retest moments and a significant reduction in the VHI score after intervention. Considering certainty of the evidence, the level of evidence was very low in both the reliability and responsiveness stages. The analyzed studies did not evaluate observational errors, and hence, they were not considered in this review.

CONCLUSION

The VHI proved to be reliable and responsive in measuring voice handicap. However, it should be used with caution, as there is heterogeneity, a risk of bias, and no adherence to the analysis of observational error.