TABLE 3.
Means (standard deviation) or percentages in variables by marijuana use trajectory group
| Marijuana Trajectory Groups | |||||
|---|---|---|---|---|---|
| No or low users |
Increasing users |
Moderate users |
Chronic users |
Whole sample |
|
| (64%, n=519) | (10%, n=81) | (12%, n=99) | (14%, n=117) | (N=816) | |
| Demographic variables | |||||
| Females | 68% (n=353) | 48% (n=39) | 57% (n=56) | 38% (n=44) | 60% (n=324) |
| African-American | 53% (n=276) | 54% (n=44) | 48% (n=48) | 49% (n=57) | 52% (n=425) |
| Age (T1) | 14.09 (1.33) | 14.19 (1.33) | 13.89 (1.27) | 13.65 (1.11) | 14.01 (1.30) |
| Control variables | |||||
| Depressive symptoms (T1) | 1.60 (0.89) | 1.69 (0.92) | 1.66 (0.83) | 1.70 (0.92) | 1.63 (0.89) |
| Low self-control (T1) | 2.10 (0.61) | 2.39 (0.61) | 2.29 (0.61) | 2.46 (0.62) | 2.20 (0.62) |
| Delinquency (T1) | 0.42 (0.44) | 0.66 (0.60) | 0.59 (0.63) | 0.81 (0.67) | 0.52 (0.54) |
| Alcohol use (T1) | 0.28 (0.44) | 0.32 (0.42) | 0.38 (0.55) | 0.48 (0.47) | 0.33 (0.46) |
| Cigarette use (T1) | 0.30 (0.70) | 0.37 (0.71) | 0.48 (0.82) | 0.43 (0.76) | 0.34 (0.73) |
| Illicit drug use other than marijuana (T1) | 0.03 (0.17) | 0.04 (0.25) | 0.02 (0.20) | 0.07 (0.33) | 0.03 (0.21) |
| Outcome variable at T5 | |||||
| Tobacco dependence | 10% (n=52) | 37% (n=30) | 24% (n=24) | 51% (n=60) | 20% (n=166) |
Note. Answer options for depressive symptoms ranged from “not at all (0)” to “extremely (3).” Answer options for low self-control ranged from “completely false (1) to completely true (4).” Answer options for delinquency ranged from “never (0)” to “five or more times (4).” Answer options for alcohol use ranged from “none (0)” to “three or more drinks every day (4).” Answer options for cigarette use ranged from “none (0)” to “more than one pack a day (5).” Answer options for illicit drug use other than marijuana ranged from “never (0)” to “once a week or more (4).