title: External Validation of the Acoustic Voice Quality Index Version 03.01 With Extended Representativity.
abstract: OBJECTIVE
  The Acoustic Voice Quality Index (AVQI) is an objective method to quantify the severity of overall voice quality in concatenated continuous speech and sustained phonation segments. Recently, AVQI was successfully modified to be more representative and ecologically valid because the internal consistency of AVQI was balanced out through equal proportion of the 2 speech types. The present investigation aims to explore its external validation in a large data set.
  
  
  METHODS
  An expert panel of 12 speech-language therapists rated the voice quality of 1058 concatenated voice samples varying from normophonia to severe dysphonia. The Spearman rank-order correlation coefficients (r) were used to measure concurrent validity. The AVQI's diagnostic accuracy was evaluated with several estimates of its receiver operating characteristics (ROC).
  
  
  RESULTS
  Finally, 8 of the 12 experts were chosen because of reliability criteria. A strong correlation was identified between AVQI and auditoryperceptual rating (r = 0.815, P = .000). It indicated that 66.4% of the auditory-perceptual rating's variation was explained by AVQI. Additionally, the ROC results showed again the best diagnostic outcome at a threshold of AVQI = 2.43.
  
  
  CONCLUSIONS
  This study highlights external validation and diagnostic precision of the AVQI version 03.01 as a robust and ecologically valid measurement to objectify voice quality.
authors.affiliation: Faculty of Medicine and Health Sciences, University of Antwerp, Belgium Medical School, Hochschule Fresenius University of Applied Sciences, Hamburg, Germany ben.barsties@t-online.de.
authors.forename: Ben
authors.initials: B
authors.lastname: Barsties
authors.affiliation: Faculty of Medicine and Health Sciences, University of Antwerp, Belgium European Institute for ORL, Sint-Augustinus Hospital, Antwerp, Belgium Faculty of Education, Health & Social Work, University College Ghent, Belgium.
authors.forename: Youri
authors.initials: Y
authors.lastname: Maryn
mesh_terms: D000162:Acoustics; D000328:Adult; D000368:Aged; D055154:Dysphonia / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006685:Hoarseness / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013018:Sound Spectrography / Q000379:methods*; D013061:Speech Acoustics; D013070:Speech Therapy; D014833:Voice Quality; D055815:Young Adult
keywords: acoustic analysis; laryngology; larynx; otolaryngology; voice; voice disorders