title: [Psychoacoustic scaling of acoustic voice parameters by multicenter voice ratings].
abstract: BACKGROUND
  The purpose of the study was to analyze if perceptual voice quality ratings of the well-known RBH rating procedure (a 4-point scale of roughness, breathiness, and hoarseness) covary with acoustical voice parameters.
  
  
  METHODS
  120 voice samples from subjects with healthy and hoarse voices were rated on the RBH-index in a multicenter study with 31 raters. Multivariate regression tree analysis classified the perceptual ratings as "gold standard". Voice samples were acoustically analyzed with a feature extraction method. Feedforward-networks were trained to selected acoustical parameters having highest "relative importance" in the regression trees. Based on the best classifier, a computer program consisting of 50 simultaneous working networks was developed.
  
  
  RESULTS
  Mean probabilities for correct classifications were found at 0.65-0.85, implying a significance level over chance (0.25). Classifications of the program matched in 40% with a priori values in the categories roughness combined with breathiness, and in 65% in at least one domain.
  
  
  CONCLUSIONS
  The new method described here provides a psychoacoustically based "objective" classification of hoarse voices, which seems to enable future analysis of new parameters (like GNE), which may even improve the present results.
authors.affiliation: Klinik für Phoniatrie und Pädaudiologie, Medizinische Hochschule Hannover. Schoenweiler.Rainer@MH-Hannover.de
authors.forename: R
authors.initials: R
authors.lastname: Schönweiler
authors.forename: P
authors.initials: P
authors.lastname: Wübbelt
authors.forename: M
authors.initials: M
authors.lastname: Hess
authors.forename: M
authors.initials: M
authors.lastname: Ptok
mesh_terms: D000162:Acoustics; D000465:Algorithms; D005260:Female; D006685:Hoarseness / Q000175:diagnosis; D006801:Humans; D008297:Male; D010699:Phonation; D011571:Psychoacoustics; D012044:Regression Analysis; D012984:Software; D014833:Voice Quality