ObjectiveAs part of a prospective study of possible effects of early-life otitis media on speech, language, cognition, and psychosocial development, we evaluated hearing both during episodes of middle-ear effusion (MEE) and when MEE was not present. The objective of this report is to describe age-specific hearing threshold levels in relation to the presence or absence of MEE in a large sample of young children.DesignParticipants were 1055 children drawn from a sample of 6350 children who were enrolled in the larger study by 2 mo of age. Otologic evaluation of each child was conducted at least monthly. The protocol of the larger study called for hearing evaluations 1) after 8 wk of continuous unilateral or bilateral MEE and every 4 wk thereafter until one test had been conducted when MEE was no longer present; 2) immediately before developmental testing; and 3) in a sample of children without MEE to obtain age-specific normative data.ResultsResults are presented by testing technique, age group, and middle-ear condition. In general, hearing threshold levels were highest in the youngest children tested with visual reinforcement audiometry and lowest in the oldest children tested with conventional audiometry. In general also, thresholds were lowest in children with normal middle-ear status, intermediate in children with unilateral MEE, and highest in children with bilateral MEE. On average, the presence of bilateral MEE was associated with hearing threshold levels 10 to 15 dB higher than the normative values for the corresponding age group.ConclusionsIn infants and young children, audiometric results are influenced by testing technique, age group, and the presence or absence of effusion in each ear.