The introduction of additional controls in the net models generally leads to a decrease in the already fairly modest associations of baseline smoking and nicotine dependence with subsequent suicide ideation. (Table 3) It should be noted that even though some of the control variables are highly inter-correlated, no evidence of multicollinearity can be found using standard tests (i.e., examination of the condition number of the predictor variable covariance, inspection for high negative correlations in the coefficient variance-covariance matrix, comparison of increases in the 95% CI’s in the net models versus the gross models). While the sign pattern in the net models holds up with the introduction of the additional controls (88% of the ORs remain elevated), none of these ORs is significant at the .05 level. Furthermore, the dose-response pattern found in the gross coefficients virtually disappears in the net models. In the case of suicide plans, in comparison, the sign pattern remains (88% of the ORs remain elevated) and the proportion of ORs that are statistically significant (17%, 3/17) is the same as in the gross models. Furthermore, some
