Table 4.

Comparison of beta coefficients for dilution-adjusted MUF linear regression models. Models 1 and 2 predict ${\text{MUF}}_{\text{SG}}$ and ${\text{MUF}}_{\mathrm{CRE}\_2}$ concentrations by water treatment plant fluoridation levels before and after controlling for covariates.

Covariates	Model 1 Log ${\text{MUF}}_{\text{SG}}$ ($n=\mathrm{1,136}$)			Model 2a Log ${\text{MUF}}_{\mathrm{CRE}\_2}$ ($n=900$)
	$R^2$	$\mathrm{B}\text{coefficient}$	95% CI	$R^2$	$\mathrm{B}\text{coefficient}$	95% CI
Unadjusted Model
WTP fluoride level	0.24	0.49	0.44, 0.54	0.26	0.53	0.47, 0.59
Adjusted Model	0.33			0.35
WTP fluoride level	0.22	0.48	0.43, 0.53	0.24	0.52	0.46, 0.57
Prepregnancy BMI	0.00	0.00	$-0.00$, 0.00	0.01	$-0.01$	$-0.01$, 0.00
Maternal age at delivery	0.02	0.01	0.00, 0.01	0.02	0.01	0.00, 0.01
Smoking during pregnancy	0.00	0.01	$-0.01$, 0.03	0.00	$-0.00$	$-0.03$, 0.02
No. glasses of water	0.02	0.02	0.01, 0.03	0.03	0.02	0.01, 0.02
No. cups of black tea	0.07	0.12	0.10, 0.14	0.05	0.10	0.08, 0.13
No. cups of green tea	0.00	0.08	0.01, 0.15	0.00	0.06	$-0.02$, 0.13

Note: BMI, body mass index; CI, confidence interval; CRE, creatinine; MUF, maternal urinary fluoride; SG, specific gravity; WTP, water treatment plant.

^aData not shown for ${\text{MUF}}_{\mathrm{CRE}\_1}$ because the results were identical to ${\text{MUF}}_{\mathrm{CRE}\_2}$.