Table 1. Baseline characteristics.

	Mean training data (n=194)	(SD)	Mean test data (n=133)	(SD)	t-testa	P-value
Demographics
Age at interview (years)	30.7	(7.1)	32.4	(7.1)	-2.1	0.04
Unmarried	53%		47%		1.06	0.29
Number of years of education	13.2	(1.9)	13.5	(2.2)	-1.28	0.20
Psychiatric history
Age at MD onset (years)	22.1	(9.4)	26.1	(9.5)	-3.74	0.00
History of MD	63%		44%		3.34	0.00
Number of episodes (if history of MD is present)	10.1	(20.0)	5.1	(9.1)	2.33	0.02
History of early anxiety	58%		53%		0.87	0.39
Episode prior to FF1 (training data)/FF2 (test data)
Sum of 9 MD criteria	6.3	(1.2)	6.4	(1.1)	-0.95	0.34
Duration of longest episode previous (months)	2.7	(3.0)	2.7	(2.8)	0.19	0.85
Number of episodes in year prior to interview	2.3	(2.0)	2.4	(2.3)	-0.47	0.64
Adverse life events (early and recent)
Number of lifetime traumas	2.3	(1.8)	2.0	(1.6)	1.81	0.07
Number of stressful life events past year	4.0	(2.4)	2.7	(2.0)	5.16	0.00

^aWelch's t-test