Table 2.
Descriptive statistics
| Variable | Range | Person levela %/M (SD) | Wave levelb %/M (SE) |
|---|---|---|---|
| Driving after substance use, past 2 weeks, % | |||
| Marijuana | 0,1 | 18.0 (38.41) | 8.9 (0.55) |
| 5+ Drinks | 0,1 | 19.8 (39.84) | 8.7 (0.53) |
| Social roles | |||
| Live with parents (vs. other), % | 0,1 | 59.6 (49.07) | 31.7 (0.88) |
| Married (vs. other), % | 0,1 | 36.3 (48.10) | 21.7 (0.78) |
| Parent (vs. other), % | 0,1 | 32.9 (46.99) | 19.2 (0.83) |
| College attendance, % | 1–3 | ||
| None | 82.2 (38.28) | 58.2 (0.75) | |
| Part time | 27.0 (44.40) | 10.1 (0.49) | |
| Full time | 63.7 (48.09) | 31.7 (0.67) | |
| Employment, % | 1–3 | ||
| None | 50.1 (50.00) | 23.2 (0.74) | |
| Part time | 59.8 (49.03) | 30.2 (0.73) | |
| Full time | 72.8 (44.49) | 46.5 (0.80) | |
| Mediators | |||
| Risk of regular marijuana usec, M | 1–4 | 3.2 (0.80) | 3.2 (0.02) |
| Risk of 5+ drinking 1–2 times on weekendsc, M | 1–4 | 3.2 (0.72) | 3.2 (0.02) |
| Evenings outd, M | 1–6 | 2.8 (1.03) | 2.7 (0.02) |
| Religiosity, M | 1–4 | 2.5 (0.90) | 2.5 (0.02) |
| Covariates | |||
| Average weekly miles drivene, M | 1–6 | 3.9 (1.24) | 3.9 (0.03) |
| 30-day alcohol use frequencyf, M | 1–7 | 2.7 (1.35) | 2.7 (0.03) |
| 30-day marijuana use frequencyf, M | 1–7 | 1.6 (1.25) | 1.5 (0.03) |
| Modal age, M | 19–30 | 23.5 (2.12) | 24.1 (0.03) |
| Male (vs. female), % | 0,1 | 48.4 (49.97) | 44.8 (1.36) |
| Race/ethnicity, % | |||
| Black | 0,1 | 12.1 (32.56) | 9.7 (0.91) |
| Hispanic | 0,1 | 13.3 (34.01) | 12.1 (0.98) |
| Other | 0,1 | 9.0 (28.55) | 8.0 (0.74) |
| White | 0,1 | 65.6 (47.49) | 70.1 (1.32) |
Notes: n(unweighted) = 7,067 waves from 1,873 individuals. All estimates obtained from weighted models.
Person-level percentages indicate the percentage of individuals who ever reported the specified measure. Person-level means indicate the average across all individual averages. Because these estimates were measured at the person level, no adjustment for clustering was needed and variance is reported using standard deviations (SD).
Wave-level percentages indicate the percentage of all waves that involved the specified measure. Wave means indicate the average value across all waves. Estimates obtained from models accounting for clustering by respondent and thus report standard errors (SE).
Risk responses: 1 = no risk, 2 = slight risk, 3 = moderate risk, 4 = great risk.
Evenings out responses: 1 = less than one, 2 = one, 3 = two, 4 = three, 5 = four or five, 6 = six or seven.
Miles driven responses: 1 = none, 2 = 1–10 miles, 3 = 11–50 miles, 4 = 51–100 miles, 5 = 101–200 miles, 6 = more than 200 miles.
Use frequency responses: 1 = 0 occasions, 2 = 1–2, 3 = 3–5, 4 = 6–9, 5 = 10–19, 6 = 20–39, 7 = 40 or more occasions.