BACKGROUND: To prevent later developmental impairments, myringotomy with the i nsertion of tympanostomy tubes has often been undertaken in young children who h ave persistent otitis media with effusion. We previously reported that prompt as compared with delayed insertion of tympanostomy tubes in children with persiste nt effusion who were younger than three years of age did not result in improved developmental outcomes at three or four years of age. However, the effect on the outcomes of schoolage children is unknown. METHODS: We enrolled 6350 healthy in fants younger than 62 days of age and evaluated them regularly for middle-ear e ffusion. Before three years of age, 429 children with persistent middle-ear eff usion were randomly assigned to have tympanostomy tubes inserted either promptly or up to nine months later if effusion persisted. We assessed developmental out comes in 395 of these children at six years of age. RESULTS: At six years of age , 85 percent of children in the early treatment group and 41 percent in the dela yed treatment group had received tympanostomy tubes. There were no significant d ifferences in mean (±SD) scores favoring early versus delayed treatment on any of 30 measures, including the Wechsler Full-Scale Intelligence Quotient (98±13 vs. 98±14); Number of Different Words test, a measure of word diversity (183± 36 vs. 175±36); Percentage of Consonants Correct-Revised test, a measure of sp eech-sound production (96±2 vs. 96±3); the SCAN test, a measure of central au ditory processing (95±15 vs. 96±14); and several measures of behavior and emot ion. CONCLUSIONS: In otherwise healthy children younger than three years of age who have persistent middle-ear effusion within the duration of effusion that we studied, prompt insertion of tympanostomy tubes does not improve developmental outcomes at six years of age. BACKGROUND: To prevent later developmental impairments, myringotomy with the i nsertion of tympanostomy tubes has often been undertaken in young children who h ave persistent otitis media with effusion. We previously reported that prompt as compared with delayed insertion of tympanostomy tubes in children with persiste nt effusion who were younger than three years of age did not result in improved developmental outcomes at three or four years of age. However, the effect on the outcomes of schoolage children is unknown. METHODS: We enrolled 6350 healthy in fants younger than 62 days of age and evaluated them regularly for middle-ear e ffusion. 429 children with persistent middle-ear eff usion were randomly assigned to have tympanostomy tubes inserted either promptly or up to nine months later if effusion persisted. We assessed developmental out comes in 395 of these children at six years of age. RESULTS: At six years of age, 85 percent of children in the earl There were no significant differences in mean (± SD) scores favoring early versus delayed treatment on any of 30 measures, including the Wechsler Full-Scale Intelligence Quotient ( 98 ± 13 vs. 98 ± 14); Number of Different Words test, a measure of word diversity (183 ± 36 vs. 175 ± 36); Percentage of Consonants Correct-Revised test, a measure of spech-sound production ± 2 vs. 96 ± 3); the SCAN test, a measure of central au ditory processing (95 ± 15 vs. 96 ± 14); and several measures of behavior and emotions. CONCLUSIONS: In otherwise healthy children younger than three years of age who have persistent middle-ear effusion within the duration of effusion that we studied, prompt insertion of tympanostomy tubes does not improve developmental outcomes at six years of age.