Table 2. Characteristics of demographic variables in the two samples.

	Sample I		Sample II
	BD (N = 280)	Controls (N = 200)	BD (N = 435)	Controls (N = 1699)
	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)
Age at interview, years	34.80 (11.5)	47.30 (8.7)	36.40 (12.5)	46.20 (14.7)
Education, years	13.15 (5.66)	10.92 (4.38)	11.74 (4.78)
	N (%)	N (%)	N (%)	N (%)
Gender
Male	137 (48.6)	62 (31.0)	198 (45.5)	788 (46.4)
Marital status
Married	95 (34.1)	118 (59.0)	100 (23.0)
Separated, divorced, widowed	52 (18.3)	30 (14.8)	60 (13.9)
Never married	133 (47.6)	52 (26.2)	275 (63.1)