. 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 4.

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


Variable	Total IGF-I^aa	PAPP-A2^a	Intact IGFBP-3	Total IGFBP-3	Percentage of free to total IGF-I^a
Free IGF-I (n = 431)^a
R	0.39	−0.03	0.12	0.27	0.61
P value	<0.0001	0.59	0.01	<0.0001	<0.0001
Total IGF-I (n = 431)^a
r		−0.47	0.75	0.10	−0.49
P value		<0.0001	<0.0001	0.04	<0.0001
PAPP-A2 (n = 431)^a
R			−0.65	0.29	0.38
P value			<0.0001	<0.0001	<0.0001
Intact IGFBP-3 (n = 431)
R				−0.14	−0.53
P value				0.003	<0.0001
Total IGFBP-3 (n = 431)
R					0.17
P value					0.0003

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.