title: Classification of voice disorder in children with cochlear implantation and hearing aid using multiple classifier fusion.
abstract: BACKGROUND
  Speech production and speech phonetic features gradually improve in children by obtaining audio feedback after cochlear implantation or using hearing aids. The aim of this study was to develop and evaluate automated classification of voice disorder in children with cochlear implantation and hearing aids.
  
  
  METHODS
  We considered 4 disorder categories in children's voice using the following definitions: Level_1: Children who produce spontaneous phonation and use words spontaneously and imitatively. Level_2: Children, who produce spontaneous phonation, use words spontaneously and make short sentences imitatively. Level_3: Children, who produce spontaneous phonations, use words and arbitrary sentences spontaneously. Level_4: Normal children without any hearing loss background. Thirty Persian children participated in the study, including six children in each level from one to three and 12 children in level four. Voice samples of five isolated Persian words "mashin", "mar", "moosh", "gav" and "mouz" were analyzed. Four levels of the voice quality were considered, the higher the level the less significant the speech disorder. "Frame-based" and "word-based" features were extracted from voice signals. The frame-based features include intensity, fundamental frequency, formants, nasality and approximate entropy and word-based features include phase space features and wavelet coefficients. For frame-based features, hidden Markov models were used as classifiers and for word-based features, neural network was used.
  
  
  RESULTS
  After Classifiers fusion with three methods: Majority Voting Rule, Linear Combination and Stacked fusion, the best classification rates were obtained using frame-based and word-based features with MVR rule (level 1:100%, level 2: 93.75%, level 3: 100%, level 4: 94%).
  
  
  CONCLUSIONS
  Result of this study may help speech pathologists follow up voice disorder recovery in children with cochlear implantation or hearing aid who are in the same age range.
authors.affiliation: Islamic Azad University, Mashhad Branch, Department of Biomedical Engineering, Young Researchers Club, Iran. zmbe85@yahoo.com
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Mahmoudi
authors.forename: Saeed
authors.initials: S
authors.lastname: Rahati
authors.forename: Mohammad Mahdi
authors.initials: MM
authors.lastname: Ghasemi
authors.forename: Vahid
authors.initials: V
authors.lastname: Asadpour
authors.forename: Hamid
authors.initials: H
authors.lastname: Tayarani
authors.forename: Mohsen
authors.initials: M
authors.lastname: Rajati
mesh_terms: D002648:Child; D002675:Child, Preschool; D002965:Classification / Q000379:methods*; D019929:Cochlear Implantation; D005260:Female; D006310:Hearing Aids; D034381:Hearing Loss / Q000150:complications / Q000503:physiopathology; D006801:Humans; D007802:Language; D008297:Male; D010699:Phonation / Q000502:physiology; D014831:Voice / Q000502:physiology; D014832:Voice Disorders / Q000145:classification* / Q000150:complications / Q000503:physiopathology / Q000601:surgery*