title: A normative study of otoacoustic emissions, ear asymmetry, and gender effect in healthy schoolchildren in Slovakia.
abstract: OBJECTIVE
  The aim of this normative study was to examine cochlear status and possible ear asymmetry and gender effect in transient evoked and distortion product otoacoustic emissions in a group of healthy 12-year-old children in Slovakia.
  
  
  METHODS
  Two hundred and twenty-nine 12-year-old children from Slovakia with normal hearing were included in this study. Adolescents with acute infection, abnormal otoscopic findings and abnormal tympanometry were excluded. Pure tone audiometry was performed in standard conditions in a sound proof room. Recordings of transient evoked (TE) and distortion product otoacoustic emissions (DPOAEs) were performed using an ILO 292 USB Echoport. Parameters of hearing thresholds and OAEs were compared using correlation analysis and Wilcoxon test.
  
  
  RESULTS
  We found highly statistically significant associations between the hearing thresholds for the left and right ears. When comparing pure tone audiometry with OAEs no significant correlation was found. In TEOAE a significant gender effect and side effect in TEOAE SNR were found. On the other hand there was no side effect in TEOAE response level. In DPOAE neither gender nor side effects were determined.
  
  
  CONCLUSIONS
  This is the first comprehensive information on cochlear status among Slovak adolescents. The TEOAEs were significantly higher in girls than boys, but the ear asymmetry in TEOAE was not significant. For DPOAE responses ear asymmetry and gender did not play a role. The data obtained are a basis for population hearing screening, especially for hearing screening programs in infants and children in Slovakia. Moreover data from particular age group represent a link between data from infants and adults.
authors.affiliation: Pediatric Otorhinolaryngology, Department of Medical Faculty of Comenius University, Children's University Hospital, Limbová 1, 833 40 Bratislava, Slovakia. gabikad@yahoo.com
authors.forename: Gabriela
authors.initials: G
authors.lastname: Pavlovcinová
authors.forename: Janka
authors.initials: J
authors.lastname: Jakubíková
authors.forename: Tomás
authors.initials: T
authors.lastname: Trnovec
authors.forename: Kinga
authors.initials: K
authors.lastname: Lancz
authors.forename: Sona
authors.initials: S
authors.lastname: Wimmerová
authors.forename: Eva
authors.initials: E
authors.lastname: Sovcíková
authors.forename: Lubica
authors.initials: L
authors.lastname: Palkovicová
mesh_terms: D000158:Acoustic Impedance Tests; D001301:Audiometry, Pure-Tone; D002648:Child; D003051:Cochlea / Q000502:physiology*; D004423:Ear / Q000502:physiology; D005260:Female; D006304:Health Status; D006311:Hearing Disorders / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008403:Mass Screening; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D012737:Sex Factors; D018154:Slovakia / Q000453:epidemiology; D013334:Students / Q000706:statistics & numerical data*