Table 1.
Comparison of IDUs recruited using targeted sampling and RDS, San Francisco, 2005
| Variable | RDS (NHBS) (n = 534) | TS (UHS) (n = 651) | |||
|---|---|---|---|---|---|
| Crude (%) | Adjusted (%) | Adjusted, 95% CI | Crude (%) | Unadjusted 95% CI | |
| Age (years) | |||||
| 18–20 | 0.0 | 0.0 | – | 0.2 | 0.0–99.0 |
| 21–25 | 2.1 | 1.1 | 0.3–1.9 | 2.2 | 1.2–3.7 |
| 26–30 | 1.9 | 1.6 | 0.6–2.5 | 4.9 | 3.4–7.0 |
| 31–35 | 6.5 | 7.9 | 4.4–11.9 | 6.6 | 4.9–8.9 |
| 36–40 | 16.1 | 17.5 | 13.6–22.4 | 10.8 | 8.5–13.5 |
| 41–45 | 19.1 | 19.7 | 14.1–26.7 | 18.7 | 15.9–22.0 |
| 46–50 | 22.4 | 19.8 | 15.2–24.9 | 24.7 | 21.5–28.3 |
| ≥51 | 31.9 | 32.2 | 26.1–38.4 | 32.0 | 28.4–35.7 |
| Race/ethnicity | |||||
| Native American | 2.5 | 5.8 | 2.2–9.5 | 2.5 | 1.5–4.0 |
| Asian | 0.4 | 0.6 | 0.0–1.9 | 0.2 | 0.0–1.0 |
| African American | 32.6 | 35.7 | 29.3–44.0 | 49.3 | 45.0–53.0 |
| Native Hawaiian/Pacific Islander | 0.4 | 0.5 | 0.0–1.2 | 0.3 | 0.0–1.2 |
| Non-Hispanic White | 40.8 | 35.3 | 28.9–41.8 | 35.8 | 3.2–39.6 |
| Hispanic | 10.5 | 12.9 | 6.7–18.6 | 7.3 | 5.4–9.6 |
| Other | 1.9 | 1.5 | 0.5–3.3 | 4.8 | 3.3–6.8 |
| Mixed | 11.1 | 7.6 | 5.4–10.2 | NA | NA |
| Gender | |||||
| Male | 73.6 | 71.3 | 64.4–78.5 | 71.3 | 67.6–74.7 |
| Female | 24.5 | 26.1 | 19.4–33.1 | 25.2 | 21.9–28.74 |
| Transgender | 1.9 | 2.6 | 0.7–4.4 | 3.5 | 2.3–5.3 |
| Ever tested for HIV | |||||
| No | 2.7 | 2.6 | 1.3–4.0 | 1.0 | 0.4–2.1 |
| Yes | 97.3 | 97.4 | 95.9–98.8 | 99.0 | 98.0–99.6 |
| Negative | 79.9 | 79.5 | 74.4–84.7 | 86.5 | 83.6–89.0 |
| Self-reported HIV status | |||||
| Positive | 11.9 | 13.0 | 8.7–17.6 | 9.7 | 7.6–12.3 |
| Did not receive results | 5.2 | 4.3 | 2.4–6.6 | 2.9 | 1.8–4.6 |
| Indeterminate | 0.2 | 0.7 | 0.0–1.6 | 0 | 0 |
| Never tested | 2.7 | 2.6 | 1.2–4.1 | 1.0 | 0.4–2.1 |
| Ever tested positive for HCV | 59.5 | 55.9 | 49.8–63.1 | 69.7 | 65.9–73.1 |
| Ever participated in alcohol/drug treatment programs | 68.6 | 65.7 | 60.3–71.9 | 74.8 | 71.3 -78.1 |
| Programs used in the past 12 months | |||||
| Methadone maintenance | 8.0 | 5.8 | 3.7–8.2 | 19.2 | 16.3–22.5 |
| Methadone detoxification | 6.5 | 5.4 | 3.5–7.6 | 14.1 | 11.6–17.1 |
| In-patient drug treatment | 7.8 | 5.1 | 3.2–7.1 | 3.7 | 2.4–5.5 |
| Residential drug treatment | 5.6 | 6.7 | 3.7–9.8 | 9.2 | 7.1–11.8 |
| Outpatient drug treatment | 7.2 | 5.0 | 3.5–7.7 | 4.3 | 2.9–6.2 |
| Alcoholics anonymous | 5.9 | 6.8 | 4.2–10.5 | 11.8 | 9.5–14.6 |
| Narcotics anonymous | 5.6 | 5.3 | 3.3–8.3 | N/A | N/A |
| Purchased syringes at pharmacy in 12 months | 16.8 | 17.0 | 11.9–24.1 | 9.2 | 7.1–11.8 |
| Obtained syringes via SEP in the past 12 months | 86.8 | 81.8 | 76.2–86.7 | 95.4 | 93.4–96.8 |
Numbers in bold are those where 95% CIs did not overlap. NA = not available.