The costs and traffic safety impacts of the four negligent operator treatments--Warning Letter (W/L), Group Educational Meeting (GEM), Individual Hearing (I/H), and Probation Violator Hearing (P/V) are presented. The Warning Letter was projected to save 1.24 accidents per 1,000 drivers treated. While this effect size is not statistically significant, the W/L is so inexpensive that sample results project it to be cost-beneficial, with an estimated cost of $669 for each accident prevented. The remaining treatments had statistically significant impacts on accidents. The GEM is projected to save 17.12 accidents per 1,000 drivers, at a cost of $871 per prevented accident. The I/H is projected to save 18.77 accidents per 1,000 drivers at a cost of $2,309 per accident saved. The P/V is projected to save 9.16 accidents per 1,000 drivers treated, at a relatively high estimated cost of $6,139 per accident saved. The projected effect of all treatments combined was 1,155, accidents prevented per year. The W/L, GEM, I/H, and all treatments as a package are cost-beneficial, but findings for the P/V on this are equivocal. Each treatment caused a statistically significant, substantial reduction in convictions.
Samenvatting