Table 2.

Multiple regression analysis for PSA, testosterone, prostate volume and PSA density, in relation to DM, studying BMI as a confounding factor

		B	SE	t	p	95% CI
						Lower	Upper
PSA	DM	0.743	0.155	4.795∗	< 0.001	0.439	1.048
	BMI	−0.166	0.016	10.359∗	< 0.001	−0.197	−0.134
F = 87.977*, P < 0.001*, R = 0.511, R2 = 0.261
Testosterone	DM	0.400	0.165	2.420*	0.016	0.075	0.724
	BMI	−0.210	0.017	12.305*	< 0.001	−0.243	−0.176
F = 96.237*, P < 0.001*, R = 0.528, R2 = 0.279
Prostate volume	DM	4.629	1.633	2.835*	0.005	1.420	7.837
	BMI	3.011	0.168	17.883*	< 0.001	2.680	3.341
F = 136.430*, P < 0.001*, R = 0.629, R2 = 0.396
PSA density	DM	0.020	0.004	4.853*	< 0.001	0.012	0.028
	BMI	−0.006	0.000	14.784*	< 0.001	−0.007	−0.005
F = 156.697*, P < 0.001*, R = 0.621, R2 = 0.386

BMI, body mass index; CI, confidence interval; PSA, prostate-specific antigen; SE, standard error.