Development of morphosyntactic accuracy and grammatical complexity in dutch school-age children with SLI

Purpose: The purpose of this study was to identify the development of morphosyntactic accuracy and grammatical complexity in Dutch school-age children with specific language impairment (SLI). Method: Morphosyntactic accuracy, the use of dummy auxiliaries, and complex syntax were assessed using a narrative task that was administered at three points in time (T1, T2, T3) with 12-month intervals during a 2-year period. Participants were 30 monolingual Dutch children with SLI, age 6;5 (years;months) at T1; 30 typically developing peers, age 6;6 at T1; and 30 typically developing language-matched children, age 4;7 at T1. Results: On the morphosyntactic accuracy measures, the group with SLI performed more poorly than both control groups. Error rates in the group with SLI were much higher than expected on the basis of mean length of T-units and scores on standardized language tests. Percentages of dummy auxiliaries remained high over time. No group differences were found for grammatical complexity, except at T3, when the group with SLI used fewer relative clauses than the typically developing peer group. Conclusions: The narrative analysis demonstrates different developmental trajectories for morphosyntactic accuracy and grammatical complexity in children with SLI and typically developing peer and language-matched children. In the group with SLI, grammatical skills continue to develop