The acoustic voice quality index, version 2.06 and 3.01, for the Persian-speaking population

Dysphonia assessment includes approaches like acoustic analysis, which is non-invasive and easy to use and provides an understandable numerical output. The Acoustic Voice Quality Index (AVQI) is an acoustic model that can detect dysphonia. The Persian language is spoken by around 70,000,000 native speakers. Since AVQI versions 2.06 and 3.01 have not been validated for the Persian yet, this study investigated their concurrent validity and diagnostic accuracy among the Persian-speaking population.

This scale development study was conducted from 2020 to 2021 on 180 normophonic and dysphonic native Persian-speaking residents of Mashhad, Iran. Five raters rated the samples by auditory-perceptual-judgments, including Grade from the Grade-Rough-Breathy-Asthenic-Strained (an ordinal scale) and the overall dysphonia severity from the Persian version Consensus Auditory Perceptual Evaluation of Voice (a continuous scale) to investigate both versions' concurrent validity. The intra- and inter-rater reliability and concurrent validity were evaluated for both scales. Both versions' diagnostic accuracy was assessed by the receiver operating characteristic, and the optimal thresholds were determined.

AVQI-version-2-Persian thresholds of 3.47 and 4.04 provided sensitivity of 88.30% and 85.53% and specificity of 79.07% and 85.58% by the ordinal and continuous scales, respectively. AVQI-version-3-Persian thresholds of 3.07 and 3.03 also rendered sensitivity of 74.47% and 85.53%, and specificity of 97.67% and 91.35% by the ordinal and continuous scales sequentially.

The significant values of concurrent validities and diagnostic accuracies of both versions of AVQI-Persian confirmed that it can discriminate between normal and pathological voices among the Persian-speaking population. Hence, it can be used for screening or diagnosis purposes.