. Author manuscript; available in PMC: 2020 May 20.

Published in final edited form as: Eur J Endocrinol. 2020 Mar;182(3):363–374. doi: 10.1530/EJE-19-0859

Table 3.

Cross-sectional bivariate Pearson correlation between free IGF-I, total IGF-I, PAPP-A2, intact IGFBP-3, and total IGFBP-3 in males.


Variable	Total IGF-I^a	PAPP-A2^a	Intact IGFBP-3	Total IGFBP-3	Percentage of free to total IGF-I^a
Free IGF-I (n = 402)^a
R	0.32	−0.23	0.17	−0.07	0.65
P value	<0.0001	<0.0001	0.0005	0.14	<0.0001
Total IGF-I (n = 405)^a
R		−0.48	0.85	0.02	−0.51
P value		<0.0001	<0.0001	0.72	<0.0001
PAPP-A2 (n = 405)^a
r			−0.58	0.25	0.18
P value			<0.0001	<0.0001	0.0004
Intact IGFBP-3 (n = 405)
r				−0.06	−0.53
P value				0.25	<0.0001
Total IGFBP-3 (n = 405)
R					−0.08
P value					0.11

The natural log-transformation was used for statistical analysis of free and total IGF-I, PAPP-A2, and percentage of free to total IGF-I.