Abstract
Prenatal cocaine exposure places infants at risk for developmental delays, particularly language delays (Chapman, 2000; Lester, LaGasse, & Seifer, 1998), which increase the likelihood that they will require special education services as children and show poor developmental outcomes (Delgado, Vagi, & Scott, 2006). This study used second-order latent growth curve modeling to identify the trajectory of language development of infants from 12 to 36 months of age who had completed a three-year early intervention program. This study also investigated the predictive ability of six factors related to the child, family, and intervention. Child factors included sex, birthweight, and cognitive ability at 12 months, a family factor included mother's education level, and intervention factors included intervention type and age at enrollment. Results revealed that language growth across the two-year period was quadratic, with growth declining initially, then accelerating after 24 months, compared to the nationally normed sample upon which standardized language scores were based. Being a girl, being enrolled in the program soon after birth, and having higher cognitive ability at 12 months predicted higher initial language ability. Intervention group predicted growth in language, such that both intervention groups predicted less or no initial decline compared to the primary care non-intervention group, and the center-based intervention group showed faster acceleration after 24 months compared to the home-based intervention group. Implications of these results on the research literature and practical applications were discussed.