Table 4.
Parameter estimates (b) for state characteristics from simple linear regression, forward-selection multiple linear regression, and robust multiple linear regression models, in which the dependent variable is the natural log of the reporting ratio in 1999–2009
| Variable | Simple |
Multipleb |
Robust multiple |
|||||||||
| Exp(b) | [95% CI] | p | Exp(b) | [95% CI] | p | Exp(b) | [95% CI] | p | ||||
| All MVT deaths (50 states) | ||||||||||||
| Centralized state medical examiner system | 0.91 | [0.53, 1.56] | .74 | 1.34 | [0.77, 2.32] | .30 | 1.24 | [0.73, 2.09] | .43 | |||
| UPPL – Prohibited | 1.43 | [0.63, 3.27] | .40 | |||||||||
| .08% BAC illegal per se laws in effect before 1999 | 0.84 | [0.49, 1.44] | .52 | |||||||||
| Prevalence of driving after drinking (%) | 1.31 | [0.98, 1.76] | .08 | 1.72 | [1.22, 2.42] | <.01 | 1.71 | [1.24, 2.38] | <.01 | |||
| Gallons of ethanol (per 10,000 capita) | 0.74 | [0.43, 1.27] | .28 | 0.47 | [0.26, 0.84] | .02 | 0.61 | [0.34, 1.12] | .11 | |||
| BAC testing rate among all decedents (%) | 0.99 | [0.98, 1.01] | .42 | |||||||||
| Rate of MVT deaths (per 100,000) | 1.02 | [0.97, 1.06] | .43 | 1.03 | [0.99, 1.07] | .18 | 1.03 | [0.99, 1.07] | .16 | |||
| R2 | .2042 | .3089 | ||||||||||
| Outlier state | NV | |||||||||||
| Vehicle drivers killed in crashes (44 states)a | ||||||||||||
| Centralized state medical examiner system | 1.07 | [0.61, 1.87] | .81 | 1.35 | [0.75, 2.43] | .32 | 1.78 | [1.06, 2.99] | .03 | |||
| UPPL – Prohibited | 1.20 | [0.55, 2.64] | .65 | |||||||||
| .08% BAC illegal per se laws in effect before 1999 | 0.84 | [0.48, 1.46] | .53 | |||||||||
| Prevalence of driving after drinking (%) | 1.34 | [1.00, 1.80] | .05 | 1.42 | [1.04, 1.93] | .03 | 1.56 | [1.18, 2.05] | <.01 | |||
| Gallons of ethanol (per 10,000 capita) | 1.60 | [0.71, 3.60] | .26 | |||||||||
| BAC testing rate among drivers killed in crashes (%) | 1.00 | [0.97, 1.02] | .64 | 0.99 | [0.97, 1.01] | .32 | 1.00 | [0.98, 1.01] | .62 | |||
| Rate of drivers killed in MVT crashes (per 100,000) | 0.99 | [0.93, 1.06] | .85 | |||||||||
| R2 | .1188 | .2789 | ||||||||||
| Outlier state | MD, ND, NM | |||||||||||
Notes: BAC = blood alcohol concentration; CI = confidence interval; MVT = motor vehicle traffic; UPPL = Uniform Accident and Sickness Policy Provision Law.
a
Six states (AK, NV, NH, NJ, UT, and VT) did not have reporting ratios for identified drivers because their numbers of alcohol-involved drivers were too small to be reported in the Multiple Cause of Death data;
b
the significance level for entry into the model was set at .50.