Table 1. Sample demographics.
Demographics and clinical characteristics of study participants at semester 1.
| Cluster 1 No-Low MJ&Alcohol | Cluster 2 Medium-High Alcohol/No-low MJ | Cluster 3 Medium-High Alcohol&MJ | Statistic | |||||
|---|---|---|---|---|---|---|---|---|
| Baseline demographics/clinical characteristics | (N = 487) | (N = 463) | (N = 188) | |||||
| Mean | SD | Mean | SD | Mean | SD | F | p-value | |
| Age | 18.32 | 0.91 | 18.3 | 0.73 | 18.3 | 0.63 | 0.13 | 0.882 |
| Scholastic Achievement Test (SAT) Math | 541.05 | 89.52 | 554.97 | 90.67 | 554.23 | 84.78 | 3.02 | 0.05 |
| SAT Verbal | 530.63 | 91.04 | 541.56 | 89.33 | 541.24 | 76.95 | 1.92 | 0.146 |
| SAT Writing | 534.4 | 90.45 | 553.75 | 92.03 | 544.82 | 83.87 | 4.98 | 0.007 |
| Grade Point Average (GPA) | 3.1 | 0.67 | 3.03 | 0.64 | 2.66 | 0.83 | 27.75 | <0.0001 |
| Parental Socioeconomic Status (SES) | 12.55 | 7.04 | 10.22 | 5.46 | 10.24 | 5.75 | 19.29 | <0.0001 |
| State-Trait Anxiety Inventory (STAI) | 40.13 | 9.86 | 39.23 | 10.08 | 41.45 | 10.69 | 3.24 | 0.04 |
| Beck Depression Inventory (BDI) | 3.32 | 4.44 | 3.12 | 4.43 | 4.24 | 5.06 | 4.12 | 0.02 |
| Number of Monthly Drinks | 0.4 | 0.75 | 29.29 | 32.31 | 54.54 | 42.69 | 311.17 | <0.0001 |
| Monthly Marijuana Usage (Frequency) | 0.08 | 0.39 | 0.42 | 0.71 | 13.54 | 8.13 | 1242.52 | <0.0001 |
| N(%) | N(%) | N(%) | Chi-Square | p-value | ||||
| Gender | ||||||||
| Male | 186 | 173 | 101 | 15.49 | <0.0001 | |||
| (38.2) | (37.3) | (53.7) | ||||||
| Female | 299 | 286 | 87 | |||||
| (61.8) | (62.7) | (46.3) | ||||||
| Cigarette Smoker | ||||||||
| No | 459 | 411 | 147 | 45.28 | <0.0001 | |||
| (94.2) | (88.8) | -78.2 | ||||||
| Yes | 19 | 42 | 38 | |||||
| (3.9) | (9) | (20.2) | ||||||
| Missing | 9 | 10 | 3 | |||||
| (1.9) | (2.2) | (1.6) | ||||||
| Family History for Alcoholism | ||||||||
| Negative | 378 | 365 | 139 | 0.4 | 0.397 | |||
| (77.6) | (78.8) | (73.9) | ||||||
| Positive | 109 | 98 | 49 | |||||
| (22.4) | (21.2) | (26.1) | ||||||