Otitis media and speech and language: a meta-analysis of prospective studies.

OBJECTIVE: Considerable controversy surrounds whether a history of otitis media with effusion (OME) in early childhood causes later speech and language problems. We conducted a meta-analysis of prospective studies to determine: 1) whether a history of OME in early childhood is related to receptive language, expressive language, vocabulary, syntax, or speech development in children 1 to 5 years old and 2) whether hearing loss caused by otitis media in early childhood is related to children's receptive language or expressive language through 2 years of age.
METHODS: We searched online databases and bibliographies of OME studies and reviews for prospective or randomized clinical trials published between January 1966 and October 2002 that examined the relationship of OME or OME-associated hearing loss in early childhood to children's later speech and language development. The original search identified 38 studies, of which 14 had data suitable for calculating a pooled correlation coefficient (correlational studies) or standard difference between parallel groups (group studies). Random-effects meta-analysis was used to pool data when at least 3 studies had usable data for a particular outcome.
RESULTS: We performed 11 meta-analyses. There were no significant findings for the analyses of OME during early childhood versus receptive or expressive language during the preschool years in the correlation studies. Similarly, there were no significant findings for OME versus vocabulary, syntax, or speech during the preschool years. Conversely, there was a significant negative association between OME and preschoolers' receptive and expressive language (lower language) (0.24 and 0.25 standard difference, respectively) in the group studies. Additionally, hearing was also related to receptive and expressive language in infancy (3%-9% of variance).
CONCLUSIONS: Our results indicate no to very small negative associations of OME and associated hearing loss to children's later speech and language development. These findings may overestimate the impact of OME on outcomes, because most studies did not adjust for known confounding variables (such as socioeconomic status) and excluded data not suitable for statistical pooling, especially from methodologically sound studies. Although some OME language differences were detectable by meta-analysis due to increased statistical power, the clinical relevance for otherwise healthy children is uncertain.