Tympanometric findings in children at school entry: A normative study

This study presents tympanometric normative data for Australian children at school entry in view of the lack of age-specific population-based data for this group. Participants were 327 children (164 boys, 163 girls) aged between 5 and 6 years, who had no history of middle ear infection, and passed pure-tone screening at 20 dB HL. Normative values for static admittance (SA), ear canal volume (ECV), tympanometric peak pressure, tympanometric width (TW) and tympanometric gradient were established. Based on these normative data, the use of the ASHA (1997) guidelines for medical referral, in which ECV > 1.0 ml in the presence of a flat tympanogram, SA < 0.3 ml, or TW > 200 daPa may not provide the best criteria for Australian children aged between 5 and 6 years. If SA < 0.3 ml were used instead of SA < 0.16 ml, a greater proportion of Australian children would have failed tympanometry, thus increasing the false alarm rate.