title: Increasing rate of middle ear ventilation tube insertion in children in Denmark.
abstract: OBJECTIVE
  To study the incidence rates of middle ear ventilation tube insertion in children aged 0 to 15 years in Denmark from 1997 to 2010.
  
  
  METHODS
  Using two national registers, the Danish National Health Service Register and the Danish National Patient Register, practically all cases of middle ear ventilation tube insertion performed in Denmark in the period were identified. A possible change in incidence rate over time was examined using Poisson regression analysis, while the cumulative incidence proportion was estimated using life-tables.
  
  
  RESULTS
  A total of 502,569 uni- or bilateral ventilation tube insertions distributed among 269,459 different children were identified. From 1997 to 2010 the age standardized incidence rate in 0-15-year-olds increased from 26 to 40 per 1000 person years with an estimated annual increase of 2.0% (95% confidence interval 1.9-2.1%). The largest increase in incidence rate was found in 1-year-olds with an annual increase of 4.5% (95% confidence interval 4.4-4.6%). Age-specific incidence rates remained at maximum around the age of 14 months throughout the period. The cumulative incidence proportion for the 2010 birth cohort by the time they reach the age of 5 years was estimated to 29% (95% confidence interval 28-29%).
  
  
  CONCLUSIONS
  The rate for middle ear ventilation tube insertion in Denmark was high compared to other developed countries, and an estimated 3 in 10 children born in 2010 will undergo at least one ventilation tube insertion before their fifth birthday.
authors: Department of ENT Head & Neck Surgery, Odense University Hospital, Odense, Denmark. Electronic address: bjarkid@dadlnet.dk.
authors: Bjarki Ditlev
authors: BD
authors: Djurhuus
authors: Epidemiology, Biostatistics and Biodemography, Institute of Public Health, University of Southern Denmark, Odense, Denmark.
authors: Axel
authors: A
authors: Skytthe
authors: Epidemiology, Biostatistics and Biodemography, Institute of Public Health, University of Southern Denmark, Odense, Denmark.
authors: Kaare
authors: K
authors: Christensen
authors: Department of ENT Head & Neck Surgery, Odense University Hospital, Odense, Denmark.
authors: Christian Emil
authors: CE
authors: Faber
mesh_terms: D002648:Child; D002675:Child, Preschool; D003718:Denmark / Q000453:epidemiology; D004432:Ear, Middle / Q000601:surgery*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008876:Middle Ear Ventilation / Q000706:statistics & numerical data*; D010034:Otitis Media with Effusion / Q000453:epidemiology / Q000601:surgery*
keywords: Denmark; Epidemiology; Grommet; Incidence rates; Middle ear ventilation tube; Otitis media