TABLE 1—
Sociodemographic and Drug-Related Characteristics Across Seattle-Area Studies of Injection Drug Users: Seattle, WA, 1994–2013
| Characteristic | RAVEN (n = 2780), % | Kiwi (n = 1692), % | NHBS (n = 1555), % | Needle Exchange Surveys (n = 1279), % | P |
| Age, y | < .001 | ||||
| 18–29 | 23 | 27 | 13 | 29 | |
| 30–29 | 39 | 39 | 23 | 26 | |
| 40–49 | 32 | 29 | 31 | 25 | |
| ≥ 50 | 6 | 5 | 33 | 21 | |
| Race/ethnicity | < .001 | ||||
| White | 64 | 64 | 58 | 69 | |
| Black | 23 | 15 | 18 | 8 | |
| Hispanic | 5 | 8 | 8 | 10 | |
| Other race | 6 | 12 | 4 | 7 | |
| Multiple races | 3 | 1 | 12 | 6 | |
| Gender | < .001 | ||||
| Male | 64 | 77 | 67 | 72 | |
| Female | 36 | 23 | 33 | 29 | |
| Area of residence | < .001 | ||||
| North Seattle | 23 | 19 | 17 | 25 | |
| Downtown Seattle | 24 | 24 | 44 | 30 | |
| South Seattle | 29 | 21 | 22 | 21 | |
| South King County | 18 | 24 | 13 | 16 | |
| East King County | 7 | 12 | 4 | 8 | |
| Education | < .001 | ||||
| < high-school graduate | 26 | 27 | 26 | 19 | |
| High-school graduate | 39 | 40 | 40 | 31 | |
| > high-school graduate | 34 | 33 | 33 | 50 | |
| Homelessness | < .001 | ||||
| No | 48 | 70 | 51 | 71 | |
| Yes | 52 | 30 | 49 | 29 | |
| Drug most frequently injected | < .001 | ||||
| Heroin | 66 | 50 | 81 | 84 | |
| Speedballs | 15 | 11 | 7 | 1 | |
| Cocaine | 13 | 11 | 3 | 2 | |
| Amphetamines | 7 | 28 | 10 | 13 | |
| Daily injection frequency | < .001 | ||||
| No | 41 | 60 | 32 | 32 | |
| Yes | 59 | 40 | 68 | 68 | |
| MSM | < .001 | ||||
| No | 96 | 95 | 90 | 88 | |
| Yes, not amphetamine injector | 2 | 3 | 5 | 5 | |
| Yes, amphetamine injector | 1 | 3 | 5 | 7 |
Note. MSM = men who have sex with men; NHBS = National HIV Behavioral Surveillance system; RAVEN = Risk Activity Variables, Epidemiology, and Network study.