Estimated relative risk, 95% confidence intervals, and population attributable risk (PAR) of drugs for crashes, US transit industry, 1995–2000
| Year | Type of testing | Proportion testing positive* | Estimated RR (95% CI) | PAR | PAR% | Number attributable per 1000 crashes |
|---|---|---|---|---|---|---|
| *Proportion testing positive from 1995–2000 Drug and Alcohol Testing Results Annual Reports. | ||||||
| 1995 | Post crash | 0.0217 (n = 147/6783) | 1.26 (1.06 to 1.50) | 0.0045 (0.0010 to 0.0086) | 0.45% (0.10% to 0.86%) | 4.5 (1.04 to 8.58) |
| Random | 0.0173 (n = 1390/80439) | |||||
| 1996 | Post crash | 0.0209 (n = 256/12254) | 1.41 (1.24 to 1.61) | 0.0061 (0.0036 to 0.0090) | 0.61% (0.36% to 0.90%) | 6.1 (3.6 to 9.0) |
| Random | 0.0149 (n = 1620/108347) | |||||
| 1997 | Post crash | 0.0187 (n = 260/13876) | 1.56 (1.36 to 1.78) | 0.0067 (0.0043 to 0.0093) | 0.67% (0.43% to 0.93%) | 6.7 (4.3 to 9.3) |
| Random | 0.0121 (n = 1295/107047) | |||||
| 1998 | Post crash | 0.0145 (n = 203/13968) | 1.36 (1.17 to 1.58) | 0.0038 (0.0018 to 0.0062) | 0.38% (0.18% to 0.62%) | 3.8 (1.8 to 6.2) |
| Random | 0.0107 (n = 1196/111490) | |||||
| 1999 | Post crash | 0.0152 (n = 230/15170) | 1.52 (1.22 to 1.89) | 0.0052 (0.0022 to 0.0088) | 0.52% (0.22% to 0.88%) | 5.2 (2.2 to 8.8) |
| Random | 0.0100 (n = 1198/119753) | |||||
| 2000 | Post crash | 0.0159 (n = 240/15012) | 1.70 (1.48 to 1.96) | 0.0066 (0.0045 to 0.0090) | 0.66% (0.45% to 0.90%) | 6.6 (4.5 to 9.0) |
| Random | 0.0095 (n = 1151/121668) | |||||