Table 3.

Relative Hazard per unit change in SD (95% confidence intervals in parentheses) for each of the main explanatory variables of new clinical vertebral fractures, with and without additional variables in the model.

Main Variable	Additional Variables in the Model
	None	Age	Age Race BMI	Age Race BMI Site	Age Race BMI Site LS aBMD
LS aBMD	3.5 (2.2–5.4)	3.2 (2.0–5.2)	3.3 (2.1–5.2)	3.4 (2.1–5.4)	—
FN aBMD	2.1 (1.4–3.2)	1.8 (1.2–2.9)	2.1 (1.3–3.6)	2.1 (1.2–3.5)	0.9 (0.4–1.8)
Integral vBMD	6.1 (3.4–11.1) *	5.7 (3.1–10.3)	5.8 (3.2–10.8)	9.9 (5.0–19.7) ***	9.4 (4.1–21.6)
Strength	7.6 (3.9–14.9) **	7.2 (3.6–14.1) **	7.3 (3.7–14.5) **	9.6 (4.6–19.8) ***	8.5 (3.6–20.1)
Load-to-Strength Ratio †	3.1 (2.2–4.4)	3.0 (2.1–4.3)	3.0 (2.1–4.5)	3.6 (2.5–5.1)	2.9 (1.9–4.4)
Strength-to-Density Ratio	3.4 (2.3–5.1)	3.3 (2.2–4.9)	3.3 (2.2–5.0)	3.4 (2.2–5.0)	2.2 (1.4–3.6)

Site — imaging geographic region. See Table 1 for legends and units.

^†Relative Hazard denotes an increase is risk per decrease in one standard deviation for all variables except for the load-to-strength ratio, for which it indicates an increase is risk per increase in one standard deviation.

^*p≤0.05,

^**p≤0.01,

^***p≤0.001 is for comparison vs. LS aBMD (same column) for the models in which LS aBMD was not included in the model (the last column).