Table 3.

Multilevel regression models for change from study entry for total hip, trochanter and femoral neck aligned by years from study entry.

Variables	ΔBMC
	ΔTotal hip		ΔHip trochanter		ΔFemoral neck
Random	Level 1 (within individuals)		Level 1 (within individuals)		Level 1 (within individuals)
Constant	1.43 ± 0.14		0.20 ± 0.02		0.03 ± 0.003
	Level 2 (between individuals)		Level 2 (between individuals)		Level 2 (between individuals)
	Constant	Years from start centered	Constant	Years from start centered	Constant	Years from start centered
Constant	4.03 ± 0.88	1.62 ± 0.34	0.49 ± 0.11	0.16 ± 0.04	0.02 ± 0.006	0.01 ± 0.002
Years from start centered	1.62 ± 0.34	0.62 ± 0.13	0.16 ± 0.04	0.05 ± 0.01	0.01 ± 0.002	0.004 ± 0.001
Fixed	Estimates		Estimates		Estimates
Constant	−7.37 ± 1.15		−1.76 ± 0.05		−0.53 ± 0.16
Years from start centered	−0.55 ± 0.24		−0.35 ± 0.09		NS
Years from start centered2	0.21 ± 0.02		0.05 ± 0.01		0.02 ± 0.002
Age at study start	0.33 ± 0.11		NS		0.04 ± 0.02
Sex	NS		NS		NS
Race	NS		NS		NS
Maturity	1.23 ± 0.35		0.52 ± 0.13		NS
ΔHeight	0.51 ± 0.04		0.18 ± 0.02		0.04 ± 0.003
ΔWeight	0.13 ± 0.03		0.05 ± 0.01		0.02 ± 0.004
Sport activity	1.10 ± 0.21		0.23 ± 0.09		0.14 ± 0.3
Intervention group	0.55 ±0.22		NS		NS

Fixed effect values are presented as estimated mean coefficients ± SEE [ΔBMC g from study entry].

Random effects values presented as estimated mean variance ± SEE [ΔBMC g from study entry²].

Years from start centered is years from 38 mo.

Sex (0 = male, 1 = female); race (0 = white, 1 = nonwhite); maturity (0 = pre-PHV, 1 = post-PHV); Δheight (cm) from study entry; Δωeight (kg) from study entry; sport activity (0 = no sport activities, 1 = 1 or more sports activities); intervention group (0 = controls, 1 = jumpers).

Values are p < 0.05 (mean > 2 × SE estimate) unless noted as NS (NS, not significant.)