Impact of specific language impairment and type of school on different language subsystems.

PURPOSE This study aimed to explore quantitative and qualitative effects of type of school and specific language impairment (SLI) on different language abilities. METHODS 204 Brazilian children aged from 4 to 6 years old participated in the study. Children were selected to form three groups: 1) 63 typically developing children studying in private schools (TDPri); 2) 102 typically developing children studying in state schools (TDSta); and 39 children with SLI studying in state schools (SLISta). All individuals were assessed regarding expressive vocabulary, number morphology and morphosyntactic comprehension. RESULTS All language subsystems were vulnerable to both environmental (type of school) and biological (SLI) effects. The relationship between the three language measures was exactly the same to all groups: vocabulary growth correlated with age and with the development of morphological abilities and morphosyntactic comprehension. Children with SLI showed atypical errors in the comprehension test at the age of 4, but presented a pattern of errors that gradually resembled typical development. CONCLUSION The effect of type of school was marked by quantitative differences, while the effect of SLI was characterised by both quantitative and qualitative differences.