Language abilities and nonverbal IQ in children with language impairment: inconsistency across measures.

The present study used correlation analyses to examine the extent to which language abilities are associated with nonverbal IQ in 30 children with language impairment, age 4-8 years. After controlling for age, nonverbal IQ demonstrated medium associations with composite measures of both semantic and morphosyntactic abilities (r = .46 and .45 respectively). However when only criterion-referenced measures of language were included in the analyses, no significant associations between language and nonverbal IQ were observed. In addition, individual difference scores between language and nonverbal IQ revealed that discrepancies occurred in both directions--with language exceeding nonverbal IQ in some cases and nonverbal IQ exceeding language in others. In sum, the relatively inconsistent associations between language and nonverbal IQ provided additional reason to question current practices, such as cognitive referencing and the definition of specific language impairment. Implications in regard to theoretical accounts of language impairment are also discussed.