Second to fourth digit ratio (2D:4D) and concentrations of circulating sex hormones in adulthood

Table 5 Predicted mean¹ relative concentrations of testosterone and oestradiol in men by tertiles of right and left 2D:4D and Δ_r-l.

		Right Hand					Left Hand					Δ_r-l
2D:4D tertile		mean	(95% CI)	P ² _trend	ρ ³	P ⁴	mean	(95% CI)	P ² _trend	ρ ³	P ⁴	mean	(95% CI)	P ² _trend	ρ ³	P ⁴
Testosterone:oestradiol	I	160.2	(152.6 - 167.9)	0.03	-0.06	0.03	158.9	(151.3 - 166.5)	0.19	-0.05	0.07	155.7	(148.1 - 163.4)	0.82	-0.01	0.69
	II	154.1	(146.5 - 161.8)				153.4	(145.9 - 160.9)				154.0	(146.4 - 161.7)
	III	152.1	(144.5 - 159.8)				154.2	(146.6 - 161.7)				156.5	(148.9 - 164.2)
Free testosterone:free oestradiol	I	157.0	(148.6 - 165.4)	0.02	-0.07	0.02	155.4	(147.1 - 163.8)	0.11	-0.06	0.04	151.1	(142.6 - 159.5)	0.92	-0.01	0.64
	II	148.5	(140.1 - 156.9)				147.4	(139.0 - 155.7)				148.3	(139.9 - 156.8)
	III	146.2	(137.8 - 154.6)				148.1	(139.7 - 156.4)				151.5	(143.0 - 160.0)

¹Estimates from linear mixed models of the ratio of hormone concentrations on 2D:4D tertiles with laboratory batch entered as a random intercept, adjusted for ethnicity, age at blood draw, BMI, and smoking status.
²From likelihood ratio test for linear trend across 2D:4D tertiles.
³Standardised regression coefficients (correlations) from linear mixed models of the logarithm of hormone concentration on continuous 2D:4D with laboratory batch entered as a random intercept, adjusted for ethnicity, age at blood draw, BMI, and smoking status.
⁴From likelihood ratio test of ρ.

ISSN: 1477-7827