Expressive language development in adolescents with Down syndrome and fragile X syndrome: change over time and the role of family-related factors

Table 4 Association of diagnostic group with level and change of conversational ELS measures, while controlling for CA and nonverbal cognition

Variable [β(SE), p]	Syntax complexity	Lexical diversity	Talkativeness
DS	− 0.24 (0.08), p = 0.003	− 15.9 (5.3), p = 0.004	0.49 (0.99), p = 0.6
Time	− 0.06 (0.02), p = 0.003	− 3.3 (1.7), p = 0.06	0.92 (0.21), p < 0.001
DS x Time	− 0.02 (0.03), p = 0.6	− 0.42 (2.18), p = 0.8	− 1.5 (0.4), p < 0.001

Syntax complexity was transformed with the natural logarithm prior to analysis. The coefficient for DS represents the average difference between DS and FXS at baseline in ELS. The coefficient for time is the estimated annual change in FXS and the coefficient for DS × time is the estimated difference in annual change between DS and FXS. Models include baseline CA, its interaction with time, and Leiter-R GS at each visit. Bolded values have p < 0.05
DS Down syndrome, CA chronological age, GS growth score

ISSN: 1866-1955