Table 4.

Difference in mean hormone concentrations by race/ethnicity, comparing NHANES 1988–1991 to 1999–2004.

	Race/ ethnicity	1988–1991		1999–2004
		Meana, b	95% CIc	Meana, b	95% CIc	Difference	P-value
Testosterone (ng/ml)	White	5.38	5.20, 5.56	5.28	5.08, 5.49	−0.10	0.37
	Black	5.33	4.97, 5.69	5.90	5.55, 6.26	0.57	0.02
	Mexican-American	5.29	5.12, 5.46	5.09	4.76, 5.43	−0.20	0.26
Free testosterone (ng/ml)	White	0.099	0.094, 0.104	0.096	0.091, 0.102	−0.003	0.45
	Black	0.096	0.089, 0.104	0.107	0.098, 0.117	0.011	0.04
	Mexican-American	0.099	0.095, 0.104	0.095	0.088, 0.102	−0.005	0.23
SHBG (nmol/L)	White	34.87	33.37, 36.43	33.42	31.79, 35.13	−1.45	0.15
	Black	34.37	32.22, 36.66	34.47	31.72, 37.45	0.10	0.95
	Mexican-American	33.11	31.42, 34.88	33.24	30.75, 35.93	0.13	0.93
3α-diol-G (ng/ml)	White	12.22	11.55, 12.92	10.16	9.64, 10.71	−2.06	<0.01
	Black	10.90	10.02, 11.85	10.25	9.57, 10.99	−0.65	0.24
	Mexican-American	10.73	9.96, 11.57	9.57	8.82, 10.37	−1.17	0.03
Estradiol (pg/ml)	White	35.41	33.76, 37.14	28.94	27.34, 30.63	−6.47	<0.01
	Black	40.15	38.17, 42.22	38.94	34.88, 43.47	−1.21	0.61
	Mexican-American	33.41	31.03, 35.97	26.14	23.97, 28.51	−7.27	<0.01

^aadjusted for age (1 year intervals), BMI, waist circumference, smoking, and alcohol use

^bmeans for free testosterone, SHBG, 3α-diol-G, and estradiol are geometric means

^cCI – confidence interval