Tympanometry in three-year-old children. Prevalence and spontaneous course of MEE.

Tympanometric screening was performed in January 1976 and in August 1978 on 938 healthy three-year-old children (1,866 ears), constituting more than 95% of the total population of three-year-olds living in a Danish municipality at the time of testing. All children showing abnormalities were followed by tympanometry through the subsequent six months, or until spontaneous normalization had been ascertained. The study demonstrated a high prevalence and a common spontaneous recovery of secretory otitis media. In summer as well as in winter middle ear effusion was found in about 10% of all ears, or in every eighth child. Two thirds of the ears improved spontaneously, one third to complete normalization. Middle ear function, assessed by tympanometry, is extremely labile during the preschool years and must be evaluated from a dynamic point of view. This greatly restricts the predictive value of snapshots, such as screening results. Therefore, pending complementary information from long-term cohort studies, universal impedance screening of all preschool children should not be instituted.