Table 2.
Zero-Inflated Poisson Regression Using Early Adolescent Psychopathology to Predict Lifetime Alcohol Use Disorder Symptoms by Young Adulthood.
| Alcohol Use Disorder Symptoms | ||||||||
|---|---|---|---|---|---|---|---|---|
| Zero Inflation | Symptom Count | |||||||
| OR | 95% CI | z | p | IRR | 95% CI | z | p | |
| Step 1 | ||||||||
| Age | 1.047 | .766 − 1.432 | .288 | .773 | .882 | .777 − 1.001 | −1.947 | .052 |
| Minority Status | 1.925 | 1.168 − 3.177 | 2.566 | .010 | 1.001 | .832 − 1.204 | .006 | .995 |
| Family Socioeconomic Status | .997 | .979 − 1.016 | −.280 | .779 | 1.001 | .995 − 1.008 | .386 | .699 |
| Parent Alcohol/Drug Problems | .616 | .358 − 1.061 | −1.748 | .080 | 1.006 | .829 − 1.221 | .061 | .951 |
| Child's Prior Alcohol Use | .615 | .380 − .996 | −1.978 | .048 | 1.045 | .866 − 1.260 | .456 | .648 |
| Child's Prior Alcohol Problems | .512 | .186 − 1.409 | −1.296 | .195 | 1.163 | .883 − 1.530 | 1.075 | .282 |
| CD Symptoms | 1.065 | .808 − 1.402 | .446 | .656 | 1.190 | 1.054 − 1.342 | 2.833 | .005 |
| ADHD Symptoms | .985 | .752 − 1.292 | −.106 | .916 | 1.034 | .934 − 1.145 | .644 | .520 |
| Depression | .956 | .736 − 1.241 | −.337 | .736 | 1.048 | .937 − 1.172 | .827 | .408 |
| Anxiety/Withdrawal | 1.079 | .806 − 1.445 | .510 | .610 | .858 | .774 − .952 | −2.885 | .004 |
| Step 2 | ||||||||
| CD X ADHD | .918 | .703 − 1.200 | −.629 | .529 | .946 | .872 − 1.025 | −1.355 | .175 |
| CD X Depression | .854 | .659 − 1.106 | −1.194 | .232 | 1.106 | 1.011 − 1.210 | 2.193 | .028 |
| CD X Anxiety/Withdrawal | .817 | .581 − 1.149 | −1.160 | .246 | .978 | .889 − 1.078 | −.439 | .661 |
Note. OR = odds ratio; IRR = incident rate ratio; CI = confidence interval. In this zero-inflated Poisson regression, the inflation portion of the model is a logistic regression predicting a latent subpopulation of individuals who are unable to assume AUD symptom scores besides zero (e.g., abstainers). The count portion of the model is a Poisson regression predicting the number of AUD symptoms accrued by the latent subpopulation of individuals who could assume AUD symptom scores of zero and above (e.g., regular drinkers).