Table 4. Association of BMD z score at different skeletal sites (dependent variable) with predictors in biological children.

Predictors	Z score spine		Z score total femur		Z score radius
	b	P	b	P	b	P
Age	−0.239	0.004	−0.107	<0.001	0.040	n.s.
Sex	0.182	<0.001	−0.449	<0.001	0.284	<0.001
BMI	0.143	<0.001	0.284	0.032	0.076	0.004
PAI	0.031	n.s.	0.169	<0.001	0.439	<0.001
Calcium intake	0.545	0.031	0.096	0.006	0.601	<0.001
Parent Z score spine	0.328	<0.001
Parent Z score total femur			0.259	<0.001
Parent Z score radius					0.210	<0.001

BMI = body mass index; PAI = physical activity index; b = standardized regression coefficient.