Table 2.

Age and gender distributions of the ESSENCE and non-ESSENCE groups

Age and gender distribution	Parent-completed form, n=147		Telephone interview form, n=188		Direct interview form, n=116
	ESSENCE n=48	Non-ESSENCE n=99	ESSENCE n=88	Non-ESSENCE n=100	ESSENCE n=52	Non-ESSENCE n=64
Mean age in years (SD)	3.73 (1.18)*	2.67 (1.04)	4.04 (1.25)*	3.24 (1.34)	3.36 (1.18)	3.63 (1.33)
Male gender, n (%)	36 (75)**	52 (52.5)	60 (68.2)**	51 (51)	46 (71.9)**	25 (48.1)

Notes:

^*P<0.05 for t-test pairwise comparisons in age between the ESSENCE and non-ESSENCE group;

^**P<0.02 for chi-squared test in comparisons for gender between the ESSENCE and non-ESSENCE groups.

Abbreviation: ESSENCE, Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations.