Meta-Analysis on the Validity of the Acoustic Voice Quality Index

Acoustic measurements are useful tools to objectively measure overall voice quality. The Acoustic Voice Quality Index (AVQI) has shown to be a valid multiparametric tool to objectify dysphonia severity. The increasing number of validity studies investigating AVQI's validity demands a comprehensive synthesis of the available outcomes.

The aim of the present meta-analysis is to quantify the evidence for the diagnostic accuracy of the AVQI, including its sensitivity, specificity and likelihood ratio statistics, and its concurrent validity and sensitivity to changes in auditory-perceptual voice quality ratings.

Meta-analysis SEARCH STRATEGY: MEDLINE, EMBASE, the Cochrane library and Web of Science were searched from 2010 till April 2021 with an additional manual search, using keywords related to AVQI and common terminologies of validity outcomes. Studies considering the clinical validity of AVQI (ie, diagnostic accuracy, concurrent validity and sensitivity to change), using auditory-perceptual voice quality evaluation as reference, were included.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses of Diagnostic Test Accuracy Studies (PRISMA-DTA) guidelines were used. Quality assessment of included studies was conducted using the QUADAS-2 tool. For the diagnostic accuracy of AVQI, the pooled sensitivity, specificity and likelihood ratio statistics were determined using a summary receiver operating characteristic approach. Weighted correlation coefficient measures (r_W¯) were used to assess the concurrent validity and sensitivity to change.

A total of 198 studies were screened and 33 articles were included. In total, voice samples of 11447, 10272, and 367 different subjects were considered for analysis of diagnostic accuracy, concurrent validity and change responsiveness, respectively. Satisfying diagnostic accuracy results were found with a pooled sensitivity of 0.83 (95% CI: 0.82-0.83), a pooled specificity of 0.89 (95% CI: 0.88-0.90), a pooled positive LR of 7.75 (95% CI: 6.04-9.95), a pooled negative LR of 0.20 (95% CI: 0.16-0.23), and a pooled diagnostic odds ratio of 47.13 (95% CI: 34.82-63.79). Summary receiver operating characteristic curve analysis showed an excellent AUC value of 0.937 and Q* index of 0.874. Strong correlations of r_W¯ = 0.838 for concurrent validity and r_W¯ = 0.796 for sensitivity to change were found.

Our results confirm the general clinical utility of the AVQI as a robust and valid objective measure for evaluating overall dysphonia severity across languages and study methods.