. Author manuscript; available in PMC: 2014 Jan 1.

Published in final edited form as: Neuroimage. 2012 Sep 16;64:10.1016/j.neuroimage.2012.09.021. doi: 10.1016/j.neuroimage.2012.09.021

Table 2.

Descriptive Statistics for Cognitive Data and Tests of Gender and Twin Status

Infant Cognitive Assessments	Males (n = 41)	Females (n = 32)		Singletons (n = 29)	Twins (n = 44)		Total Sample (N = 73)
Infant Cognitive Assessments	Mean (SD)		p-value	Mean (SD)		p-value	Mean (SD)
Working Memory	69 (16)	70 (14)	0.62	70 (14)	68 (16)	0.62	69 (15)
Mullen ELCS	115 (13)	113 (13)	0.52	114 (13)	114 (13)	0.70	114 (13)
NVDQ	122 (13)	120 (13)	0.54	121 (10)	121 (14)	0.89	121 (13)
VDQ	107 (13)	104 (12)	0.38	106 (13)	106 (12)	0.86	105 (13)

Results from t-tests of gender and twin status are shown for all cognitive assessments. Working memory scores reflect the percent correct using the infants’ best performance between two test administrations. Mullen Early Learning Composite Score (ELCS) is a standardized score (mean = 100, SD ± 15). Non-Verbal and Verbal Developmental Quotients (NVDQ, VDQ, respectively) are derived from combining subscales on the Mullen assessment.