Table 4a.
Model parameters from zero-inflated Poisson models predicting past year cannabis use with Peer Cannabis Use
| Cannabis Use Days in the Past Year | ||||
|---|---|---|---|---|
| Predictors | Estimate | SE | z | p |
| Count Model | ||||
| (Intercept) | 0.62 | 0.04 | 14.02 | <.001 |
| ageΔ | 0.42 | 0.02 | 21.47 | <.001 |
| agem | 0.42 | 0.02 | 24.20 | <.001 |
| Sex | 0.51 | 0.01 | 49.50 | <.001 |
| FH Alc | 0.00 | 0.01 | −0.29 | .744 |
| PeerCan | 1.01 | 0.02 | 65.97 | <.001 |
| ageΔ* PeerCan | −0.06 | 0.01 | −7.96 | .226 |
| agem * PeerCan | −0.07 | 0.01 | −10.49 | <.001 |
| ageΔ* agem * PeerCan | −0.12 | 0.01 | −19.71 | <.001 |
| Zero-Inflated Model | ||||
| (Intercept) | 5.14 | 0.42 | 12.20 | <.001 |
| ageΔ | −0.27 | 0.15 | −1.80 | .072 |
| agem | −0.07 | 0.12 | −0.57 | .569 |
| Sex | −0.43 | 0.26 | −1.63 | .104 |
| FH Alc | −0.23 | 0.29 | −0.79 | .430 |
| PeerCan | −2.10 | 0.18 | −11.53 | <.001 |
| ageΔ* PeerCan | −0.03 | 0.06 | −0.52 | .606 |
| agem * PeerCan | −0.19 | 0.09 | −2.13 | .033 |
| ageΔ* agem * PeerCan | −0.15 | 0.07 | −2.05 | .041 |
Note. Zero-inflated portion reflects likelihood of being a “zero” (i.e., no drinking reported in the past year). ageΔ = Age Change; agem = Age Cohort; FH Alc = Family history density of alcohol use disorders; PeerCan = Peer Cannabis Use