Validation of the Acoustic Voice Quality Index Version 03.01 and the Acoustic Breathiness Index in the Spanish language

Objective: The aim of this study was to validate the Acoustic Voice Quality Index 03.01 (AVQIv3) and the Acoustic Breathiness Index (ABI) in the Spanish language. Method: Concatenated voice samples of continuous speech (cs) and sustained vowel (sv) from 136 subjects with dysphonia and 47 vocally healthy subjects were perceptually judged for overall voice quality and breathiness severity. First, to reach a higher level of ecological validity, the proportions of cs and sv were equalized regarding the time length of 3 seconds sv part and voiced cs part, respectively. Second, concurrent validity and diagnostic accuracy were verified. Results: A moderate reliability of overall voice quality and breathiness severity from 5 experts was used. It was found that 33 syllables as standardization of the cs part, which represents 3 seconds of voiced cs, allows the equalization of both speech tasks. A strong correlation was revealed between AVQIv3 and overall voice quality and ABI and perceived breathiness severity. Additionally, the best diagnostic outcome was identified at a threshold of 2.28 and 3.40 for AVQIv3 and ABI, respectively. Conclusions: The AVQIv3 and ABI showed in the Spanish language valid and robust results to quantify abnormal voice qualities regarding overall voice quality and breathiness severity.