title: Duration and recurrence of otitis media with effusion in children from birth to 3 years: prospective study using monthly otoscopy and tympanometry.
abstract: OBJECTIVE
  To monitor the natural course of otitis media with effusion.
  
  
  METHODS
  Prospective, longitudinal assessment of the state of the middle ear by otoscopy and tympanometry at monthly intervals from birth to 3 years.
  
  
  METHODS
  Domiciliary visits to family homes.
  
  
  METHODS
  95 full term infants born between August 1991 and November 1993.
  
  
  METHODS
  Observed and simulated data (Monte Carlo) for the duration of single episodes of otitis media with effusion.
  
  
  RESULTS
  17 of the children had unilateral or bilateral otitis media with effusion for more than half of their first three years of life. Thirty three of the 95 children had tympanograms suggestive of otitis media with effusion at more than a third of observations; the remaining 62 had such tympanograms at less than a third of observations. The data of each group were described by a first order Markov model, yielding a mean duration of unilateral effusion episodes of 5-6 weeks in both groups; the mean duration of bilateral effusion was 6 and 10 weeks in the low and high incidence groups, respectively. However, the main difference between the groups was the time spent between episodes of effusion: effusion free periods were, on average, three times longer in the children who experienced less otitis media with effusion.
  
  
  CONCLUSIONS
  Children who are susceptible to otitis media with effusion tend to have more separate episodes of effusion rather than an increased overall duration of episodes. Such children are primarily distinguished by the likelihood with which they acquire the disease than by their ability to recover from it.
authors.affiliation: University Laboratory of Physiology, Oxford.
authors.forename: S C
authors.initials: SC
authors.lastname: Hogan
authors.forename: K J
authors.initials: KJ
authors.lastname: Stratford
authors.forename: D R
authors.initials: DR
authors.lastname: Moore
mesh_terms: D000158:Acoustic Impedance Tests; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008876:Middle Ear Ventilation; D008954:Models, Biological; D010034:Otitis Media with Effusion / Q000453:epidemiology / Q000209:etiology / Q000628:therapy; D015995:Prevalence; D011446:Prospective Studies; D012008:Recurrence