title: Influence of Glottal Fry on Acoustic Voice Assessment: A Preliminary Study.
abstract: OBJECTIVE
  This preliminary study examined the influence of glottal fry on measurement of speaking fundamental frequency (SF0) and whether sex differences influence the impact glottal fry has on SF0and cepstral peak prominence (CPP). It was hypothesized that SF0and CPP would decrease as percent glottal fry in the sample increased, with larger changes observed in the female voice.
  
  
  METHODS
  Twenty-six participants (13 men, 13 women) completed the study. Participants were recorded reading the Rainbow Passage. SF0and CPP were determined from the original sample. Percent glottal fry SF0was determined and semitone change was recalculated after removal of glottal fry from the sample. Regression analysis was used to determine the impact of glottal fry and sex on semitone change and CPP differences in SF0.
  
  
  RESULTS
  Significant differences were found for both sex and percent glottal fry on semitone change in SF0. A significant relationship was not found between CPP and semitone change when sex was accounted for.
  
  
  CONCLUSIONS
  Findings from this study indicate that the measurement of SF0for women will decline as percent of glottal fry increases. These findings have clinical implications for interpretation of SF0measurement and evidence-based outcomes for voice therapy.
authors.affiliation: Department of Communication Disorders, Auburn University, Auburn, Alabama. Electronic address: lwp0002@auburn.edu.
authors.forename: Laura W
authors.initials: LW
authors.lastname: Plexico
authors.affiliation: Department of Communication Disorders, Auburn University, Auburn, Alabama.
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Sandage
mesh_terms: D000162:Acoustics; D000328:Adult; D005260:Female; D005931:Glottis / Q000502:physiology*; D006801:Humans; D008297:Male; D010699:Phonation; D000074286:Preliminary Data; D012044:Regression Analysis; D012737:Sex Factors; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013068:Speech Production Measurement; D014732:Vibration; D014833:Voice Quality; D055815:Young Adult
keywords: Assessment; Cepstral peak prominence; Glottal fry; Speaking fundamental frequency; Vocal register