From re-analysis of data, White et al have concluded that the estimates of crash and financial savings attributable to the countermeasures funded by the Transport Accident Commission are not supportable. In this document, MUARC responds to White et al and reaches the following conclusions: (1) Scientific evaluations conducted by MUARC have shown substantial reductions in road trauma in Victoria associated with increased random breath testing using "booze buses" and the new speed camera program, each supported by TAC advertising; (2) The statistical models of monthly casualty crashes as functions of enforcement, advertising and socioeconomic factors, developed by MUARC, are sound; they have been tested by MUARC and by White et al and have been found to be satisfactory; White et al's investigations have provided additional evidence of the relationship between the TAC speed-related advertising and crashes; (3) The estimates of the points of diminishing returns of levels of TAC drink-driving and speed-related advertising, originally provided by MUARC based on statistical models, are sound; the economic analysis of advertising levels, which was based on the coefficients of advertising variables in the statistical models, has not been questioned; (4) White et al's re-analysis of the data is not relevant because of important differences in their objectives, the types of crashes analysed, the time periods covered, the treatment of levels of speed-related advertising, the inclusion of car-based random breath testing, and the assumptions made and subsequently tested; (5) White et al's so-called parsimonious three-factor model of crash variations in Victoria was based on data dredging and cannot be considered to be a valid alternative to MUARC's models; (6) White et al's test of the quantitative relationships between crashes and the enforcement and advertising variables is not valid; it is not an adequate test of the presence or absence of quantitative relationships. (A)
Samenvatting