title: Mean contact quotient using electroglottography in patients with multiple sclerosis.
abstract: OBJECTIVE
  To compare the mean and standard deviation (SD) of the contact quotient (CQ) of the sustained vowels ([a] and [e]) in multiple sclerosis (MS) patients versus controls.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Thirty-nine subjects (24 patients and 15 controls) participated in this study. Laryngeal electroglottography was performed on all subjects while phonating the vowels [a] and [e] at a comfortable pitch and loudness. The fundamental frequency, mean CQ, SDs, and jitter were computed for both vocal tasks.
  
  
  RESULTS
  The mean age of the MS group was 36.25+10.61 years. All laryngeal examinations were normal and five patients with MS had dysphonia described as voice breaks and fatigue in connected speech. For both vowels [a] and [e], the mean closed quotients were comparable in groups, MS and control (43.90 vs 53 for [a] and 44.75 vs 43.63 for [e]) with no significant difference. When comparing five MS patients with dysphonia versus controls, for the vowel [a], the mean closed quotient was significantly lower in MS patients with dysphonia (P values of 0.043).
  
  
  CONCLUSIONS
  The mean closed quotient for sustained vowels [a] and [e] are comparable in MS patients and healthy controls except in patients with dysphonia.
authors.affiliation: Department of Neurology, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Bassem
authors.initials: B
authors.lastname: Yamout
authors.forename: Zaid
authors.initials: Z
authors.lastname: Al-Zaghal
authors.forename: Iyad
authors.initials: I
authors.lastname: El-Dahouk
authors.forename: Sahar
authors.initials: S
authors.lastname: Farhat
authors.forename: Abla
authors.initials: A
authors.lastname: Sibai
authors.forename: Abdul-Latif H
authors.initials: AL
authors.lastname: Hamdan
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D055154:Dysphonia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004568:Electrodiagnosis; D005260:Female; D005931:Glottis / Q000502:physiology*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications*; D010699:Phonation; D011237:Predictive Value of Tests; D013061:Speech Acoustics; D013068:Speech Production Measurement; D014827:Vocal Cords / Q000503:physiopathology; D014833:Voice Quality