Table 1.
Characteristics of positive screening among 250 active motor vehicle operators
| Variable | n | % |
| Latent class indicatorsa | ||
| Prescription opiate analgesics | 205 | 82.0 |
| Marijuana | 178 | 71.2 |
| Cocaine | 67 | 26.8 |
| Heroin | 20 | 8.0 |
| Methadone | 26 | 10.4 |
| LSD | 21 | 8.4 |
| MDMA | 22 | 8.8 |
| Methamphetamine | 19 | 7.6 |
| GHB | 9 | 3.6 |
| PCP | 9 | 3.6 |
| Ketamine | 13 | 5.2 |
| Benzodiazepines | 76 | 30.8 |
| Barbiturates | 14 | 5.6 |
| Alcohol | ||
| No BrAC | 214 | 85.6 |
| 0 < BrAC < .05 | 23 | 9.2 |
| .05 ≤ BrAC < .08 | 7 | 2.8 |
| BrAC ≥ .08 | 6 | 2.4 |
| Demographics | ||
| Sex | ||
| Female | 93 | 37.2 |
| Male | 157 | 62.8 |
| Race | ||
| White | 154 | 61.6 |
| Black | 59 | 23.6 |
| Other | 37 | 14.8 |
| Education level | ||
| Did not complete high school | 35 | 14.0 |
| Completed high school | 71 | 28.4 |
| Some college | 98 | 39.2 |
| Completed college and beyond | 45 | 18.0 |
Notes: LSD = lysergic acid diethylamide; MDMA = methylenedioxymethamphetamine (Ecstasy); GHB = gamma hydroxybutyrate; PCP = phencyclidine; BrAC = breath alcohol concentration.
a
Percentages and n do not add up to 100% because of multiple-substance use among participants.