Table 2.
Longitudinal Multilevel Regression Model with Frequency of Marijuana Use as the Dependent Variable
| Predictor | Frequency of Marijuana Use (days used in last month) | |||
|---|---|---|---|---|
| Est. (SE) | df | t | p-value | |
| Intercept | 2.89 (0.15) | 1152.43 | 19.65 | <.001 |
| Time (linear) | 0.38 (0.05) | 1200.96 | 7.77 | <.001 |
| Gender | 1.62 (0.26) | 1145.73 | 6.17 | <.001 |
| Ethnicity/Race+ | −0.04 (0.11) | 1090.69 | −0.40 | .69 |
| Time-varying predictors | ||||
| Depression (CES-D Total) | 0.04 (0.01) | 5768.75 | 4.03 | <.001 |
| Cigarette use (frequency of use in last month) |
0.22 (0.01) | 3410.61 | 16.22 | <.001 |
| Interactions | ||||
| Time*Depression+ | 0.00 (0.00) | 4720.97 | −1.06 | .29 |
| Time*Cigarette Use | −0.01 (0.00) | 3628.37 | −3.47 | .001 |
| Gender*Depression | 0.05 (0.02) | 5827.08 | 2.72 | .007 |
| Gender*Cigarette Use | 0.09 (0.03) | 3425.48 | 3.31 | .001 |
| Depression*Cigarette Use | 0.00 (0.00) | 5982.25 | 5.90 | <.001 |
| Time*Gender*Depression+ | 0.00 (0.01) | 4694.69 | −0.38 | .70 |
| Time*Gender*Cigarette Use | −0.02 (0.01) | 3641.69 | −2.07 | .04 |
| Gender*Depression*Cigarette Use | 0.01 (0.00) | 5982.35 | 4.02 | <.001 |
Note. CES-D, Center for Epidemiological Scale-Depression.