title: Correlation Between Acoustic Measurements and Self-Reported Voice Disorders Among Female Teachers.
abstract: OBJECTIVE
  Many studies focused on teachers' voice problems and most of them were conducted using questionnaires, whereas little research has investigated the relationship between self-reported voice disorders and objective quantification of voice. This study intends to explore the relationship of acoustic measurements according to self-reported symptoms and its predictive value of future dysphonia.
  
  
  METHODS
  This is a case-control study.
  
  
  METHODS
  Voice samples of 80 female teachers were analyzed, including 40 self-reported voice disorders (VD) and 40 self-reported normal voice (NVD) subjects. The acoustic measurements included jitter, shimmer, and noise-to-harmonics ratio (NHR). Levene's t test and logistic regression were used to analyze the differences between VD and NVD and the relationship between self-reported voice conditions and the acoustic measurements. To examine whether acoustic measurements can be used to predict further voice disorders, we applied a receiver operating characteristic (ROC) curve to determine the cutoff values and the associated sensitivity and specificity.
  
  
  RESULTS
  The results showed that jitter, shimmer, and the NHR of VD were significantly higher than those of NVD. Among the parameters, the NHR and shimmer demonstrated the highest correlation with self-reported voice disorders. By using the NHR ≥0.138 and shimmer ≥0.470 dB as the cutoff values, the ROC curve displayed 72.5% of sensitivity and 75% of specificity, and the overall positive predictive value for subsequent dysphonia achieved 60%.
  
  
  CONCLUSIONS
  This study demonstrated a significant correlation between acoustic measurements and self-reported dysphonic symptoms. NHR and ShdB are two acoustic parameters that are more able to reflect vocal abnormalities and, probably, to predict subsequent subjective voice disorder. Future research recruiting more subjects in other occupations and genders shall validate the preliminary results revealed in this study.
authors.affiliation: Graduate Master's Program of Speech and Language Pathology, University of Taipei, Taipei, Taiwan; Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan.
authors.forename: Feng-Chuan
authors.initials: FC
authors.lastname: Lin
authors.affiliation: Department of Speech and Hearing Disorders and Sciences, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan; Department of Nursing, Asia University, Taichung, Taiwan. Electronic address: shchen@asia.edu.tw.
authors.forename: Sheng Hwa
authors.initials: SH
authors.lastname: Chen
authors.affiliation: Department of Health Care Management, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan; Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
authors.forename: Su-Chiu
authors.initials: SC
authors.lastname: Chen
authors.affiliation: Department of Otolaryngology, Far Eastern Memorial Hospital, Taipei, Taiwan; Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
authors.forename: Chi-Te
authors.initials: CT
authors.lastname: Wang
authors.affiliation: Department of Master's Program of Speech and Language Pathology, University of Taipei, Taipei, Taiwan.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Kuo
mesh_terms: D000162:Acoustics; D000328:Adult; D019540:Area Under Curve; D001307:Auditory Perception; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D009784:Occupational Diseases / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D016272:Occupational Health; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D000070777:School Teachers; D057566:Self Report; D012737:Sex Factors; D013068:Speech Production Measurement; D014832:Voice Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D014833:Voice Quality; D055815:Young Adult
keywords: Acoustic measurement; Dysphonia; Predictive value; Receiver operating characteristic; Sensitivity; Specificity; Teachers