Past and existing measures against drinking and driving have been based on 4 major assumptions: (1) a decrease in blood alcohol level (BAL) results in reduced accident and severity rates; (2) greater penalties for high BAL's result in greater reduction in alcohol consumption, and hence accident and severity rates; (3) the greater the likelihood of detection and conviction for high BAL's, the greater the reduction in the BAL's; and (4) the more immediate the punishment, the greater its effect and consequent reduction in accidents. The short term nature of measures aimed at reducing BAL's is stressed. As an alternative, the risk homeostasis theory of accident causation which explains accident rate fluctuations as a result of such countermeasures is outlined. It is based on a perceived level of subjective risk, to be compared with a level of desired risk, and attempts to eliminate the discrepancy; this adjustment action carries an objective accident risk from which accident rates can be calculated. The theory demonstrates the inter-changeability of immediate accident causes. Lasting accident reductions cannot be achieved by confronting road users with more opportunities to be safe, but safety can be more permanently enhanced by measures which increase peoples desire to have no accident. The target value of risk is determined by a large variety of factors - economic, cultural, and individual psychological traits and values. Cultural and individual values of risk taking cannot be directly influenced, but economic measures do offer practical possibilities for effective intervention. Examples of countermeasures which make accidents more costly to people are presented: (1) accident rates have been reduced when the expected cost of being at fault in an accident was increased (loss of military rank, referral to a psychiatrist); (2) increasing the cost of obtaining a driving licence for 16 and 17 year olds; (3) financial incentives such as free extension of the driving licence if a clean record is maintained in the previous year; and (4) bonuses to professional driver for accident free driving. The author suggests the application of incentive schemes similar to those given in industrial settings. Mention is made of a system developed in Saskatchewan which uses incentives to reduce traffic accident rates, especially among young drivers. Bonuses are given to individuals within an age group, whose performance has been satisfactory, but the size of the bonus depends on the performance not only of the individual but also of the individual's age group. For the covering abstract of the conference see IRRD 819066.
Samenvatting