Table 4.
Beta coefficients for models of urinary cotinine
| Model 1 | Model 2 | Model 3 | |
|---|---|---|---|
| R2 Model | 0.180 | 0.362 | 0.332 |
| Age | 0.029 (P=0.19) | 0.043 (P<0.05) | 0.046 (P<0.05) |
| Sex | −0.222 (P=0.59) | 0.511 (P=0.17) | 0.187 (P=0.62) |
| Race | 2.029 (P=0.47) | 2.25 (P<0.01) | 2.622 (P<0.01) |
| Years of education | −0.208 (P=0.47) | −0.053 (P=0.51) | −0.106 (P=0.20) |
| Age smoking onset | −0.098 (P=0.06) | −0.085 (P=0.07) | −0.091 (P=0.05) |
| Cigarettes per day | 0.433 (P<0.01) | 0.397 (P<0.01) | 0.333 (P<0.01) |
| Cigarettes per day2 | −0.004 (P<0.01) | 0.005 (P<0.01) | −0.004 (P<0.01) |
| BMI | −0.109 (P<0.05) | −0.135 (P<0.01) | −0.168 (P<0.01) |
| Urinary total soluble solids (mg/mL) | 1.851 (P<0.01) | ||
| Total soluble solids* race | N.S. | ||
| Urinary creatinine (mg/mL) | 3.401 (P<0.01) | ||
| Urinary creatinine * race | −0.882(P<0.05) |
Beta estimates for model 3 are based on a final model that excluded all nonsignificant interaction terms (e.g. race*education, race*cigarettes per day, race*total solids).