title: Normative Hearing Threshold Levels in Koreans with Normal Tympanic Membranes and Estimated Prevalence of Hearing Loss.
abstract: OBJECTIVE
  We investigated the normative data on the hearing threshold levels of Koreans with normal tympanic membranes and the prevalence of hearing loss (HL) and nonserviceable hearing using the data from the Korea National Health and Nutrition Examination Surveys (KNHANES) during 2010-2012.
  
  
  METHODS
  Data obtained from 16,673 participants ≥12-year-of-age with normal tympanic membranes who completed audiometric testing. We defined HL as the pure tone average (PTA) >25 dB hearing level at 500, 1,000, 2,000, and 3,000 Hz and non-serviceable hearing as PTA >40 dB hearing level.
  
  
  RESULTS
  The hearing levels at some frequencies (0.5, 3, and 6 kHz) did not differ in between the 10's and 20's, but the hearing thresholds at all frequencies increased gradually from the 30's. The hearing thresholds were higher in men than in women at high frequencies (3, 4, and 6 kHz) in the 30's and older. The prevalence of HL in either ear was 16.5% (estimates of 5.9 million), from 2.4% in the 10's up to 75.4% in the 70's and older. The prevalence of nonserviceable hearing in either ear was 6.8% (estimates of 2.5 million) and that of bilateral nonserviceable hearing was 2.5% (estimates of 0.9 million).
  
  
  CONCLUSIONS
  Hearing loss aggravated from the 30's at all frequencies and men showed poorer hearing levels than women at high frequencies. Hearing loss was a common condition and the prevalence of non-serviceable hearing in either ear, which needs hearing rehabilitation to help social communication, was 6.8%. Normative pure tone thresholds at each frequency can be used as referent values when counseling patients complaining of hearing loss.
authors.affiliation: Department of Otolaryngology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hong Ju
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Department of Otolaryngology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Myung Hoon
authors.initials: MH
authors.lastname: Yoo
authors.affiliation: Biostatistics Team, Samsung Biomedical Research Institute, Seoul, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Baek
authors.affiliation: Biostatistics Team, Samsung Biomedical Research Institute, Seoul, Korea.
authors.forename: Seon Woo
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yang-Sun
authors.initials: YS
authors.lastname: Cho
keywords: Audiometry; Hearing Loss; Normative Data; Pure Tone; Thresholds