. Author manuscript; available in PMC: 2008 Jun 26.

Published in final edited form as: Int J Lang Commun Disord. 2008 May 3;43(3):346–360. doi: 10.1080/13682820701546813

Table 1. Mean (SD) Participant Data by Group.

Group	Age in years^a	Mother's education in years^b	Performance IQ	Language composite Z-score^c
NLD	15.8 (.3)	13.7 (2.2)	102 (10)	-.18 (.76)
SLI	15.9 (.4)	12.9 (1.5)	98 (9)	-1.54 (.35)
NLI	15.9 (.4)	12.6 (1.5)	76 (6)	-1.76 (.61)

Age data missing for 1 participant in NLD group;

Mother's education data missing for 2 participants in NLD group, 1 participant in NLI group;

Z-scores based on standardization of entire longitudinal sample of 527 participants.