Table 3.

Regression coefficients of the prediction models in the training set determined by the LASSO model selection procedures (FULL model).

	Tibia lead (n=550)				Patella lead (n=548)
Variable	β	SE	P	Partial R2a	β	SE	P	Partial R2a
Intercept	-16.558	16.504	0.32		-29.827	19.140	0.12
Blood lead	1.064	0.126	<.0001	0.0924	1.854	0.186	<0.0001	0.1253
Age	0.539	0.080	<.0001	0.0585	0.861	0.118	<.0001	0.0669
Educationb
High school diploma	-4.070	1.745	0.02	0.0070	-4.249	2.574	0.10	0.0034
≥ 4 years of college	-7.173	2.093	0.0007	0.0152	-8.634	3.101	0.006	0.0097
White collar	-2.962	1.180	0.01	0.0082	-4.020	1.758	0.02	0.0066
Cumulative cigarette smoking (pack-years)	0.023	0.026	0.37	0.0010	0.066	0.038	0.09	0.0037
Smoking statusc
Former smoker	1.652	1.316	0.21	0.0020	1.753	1.947	0.37	0.0010
Current smoker	2.416	2.494	0.33	0.0012	3.780	3.692	0.31	0.0013
Serum phosphorus	-3.815	1.169	0.001	0.0138	-4.408	1.687	0.01	0.0086
Serum uric acid	1.197	0.428	0.005	0.0101	1.173	0.619	0.06	0.0045
Serum calcium	-0.345	1.317	0.79	9E-05	--	--	--
Serum creatinine	-0.238	1.283	0.85	4E-05	0.337	1.895	0.86	4E-5
Total cholesterol	0.019	0.014	0.18	0.0024	--	--	--
Total HDL	0.061	0.042	0.14	0.0028	0.134	0.060	0.03	0.0062
Hematocrit	-0.188	0.166	0.26	0.0017	-0.053	0.240	0.82	6E-5
Body mass index	0.091	0.147	0.54	0.0005	0.315	0.214	0.14	0.0027
Systolic blood pressure	0.077	0.037	0.04	0.0056	-0.029	0.058	0.62	0.0003
Diastolic blood pressure	-0.062	0.069	0.37	0.0010	-0.112	0.103	0.28	0.0015
Diagnosis of cancer	1.306	1.359	0.34	0.0012	--	--	--
Diagnosis of diabetes	4.493	2.188	0.04	0.0055	3.468	3.229	0.28	0.0015
Diagnosis of hypertension	--	--	--		4.737	1.794	0.01	0.0088
AIC	2703.5				3121.9
BIC	2707.1				3125.2
R2	0.316				0.335
Adjusted R2	0.290				0.313

^aPartial R² was calculated based on type II sum of squares.

^bReference group is high school dropout.

^cReference group is never smokers.