Scott Macdonald

The effects of introducing or lowering legal per se blood alcohol limits for driving: an international review

In this review evidence on the impact of introducing or lowering legal blood alcohol limits on traffic safety measures is examined. There is substantial variability in the types and rigour of methods used to evaluate these legislative measures, and thus not surprisingly there is variability in the results observed. In most but not all cases where an evaluation of an introduced or lowered legal limit has been conducted, some beneficial effect on traffic safety measures has been reported. These effects are in some cases relatively small, and in other cases may be temporary. In some jurisdictions, lasting reductions in collision rates have been reported. Available evidence suggests that where beneficial effects are observed they are due to general deterrence, and not restricted only to drivers at blood alcohol concentrations (BAC) specifically affected by the legal change.

REVIEW: DRUGS AND TRAFFIC COLLISIONS

Three categories of drugs, and specific commonly used drug subcategories are examined in this paper: depressants (benzodiazepines, methadone), stimulants (cocaine), and hallucinogens (cannabis). Descriptive, epidemiological studies on the incidence of drugs in driving populations show that cannabis or benzodiazepines are the most common drugs detected in most industrialized countries. The large number of experimental studies on the impact of various drugs on psychomotor performance show that the effects of the three categories of drugs and specific drugs with each category vary considerably. Some psychoactive drugs within these three categories have the potential to alter the skills required for driving. Analytic epidemiological studies, where comparison groups are utilized, provide the best information on the role of drugs in traffic crashes. The most rigorous epidemiological studies have been conducted on benzodiazepines and traffic crashes. Generally, benzodiazepine users are up to 6 times more likely to be in crashes than non-users, depending on the study; however, the effects can be mitigated by altering the mode and type of prescriptions. In terms of the other types of drugs, the research is less rigorous and has not clearly shown they are associated with increased rates of traffic crashes.

Unrecorded alcohol consumption in Ontario, Canada: estimation procedures and research implications

In 1975 the amount of alcohol consumed through unrecorded sources in Ontario was estimated to be between 4% and 6% of overall consumption of absolute alcohol. Population surveys and other data sources were used to produce more recent estimates of the amount of alcohol consumed through U-brew and U-vint production, home brewing, cross-border shopping and illegal channels. Based on converging extimates, consumption of absolute alcohol from unrecorded sources is now estimated to be about 19.5%. Generally, the data provide more support for the substitution model rather than the additive model, as declines in official sales data appear to have coincided with increases in consumption from unrecorded sources. The implications of unrecorded consumption from a research and public health perspective are discussed. [Macdonald S, Wells S, Giesbrecht N. Unrecorded alcohol consumption in Ontario, Canada; estimation procedures and research implications. Drug Alcohol Rev 1999;18:21-29]

The Impact and Effectiveness of Drug Testing Programs in the Workplace

In this chapter the impact and effectiveness of drug testing programs in the workplace (sometimes referred to as drug screening programs) are examined. It will become clear in this review that few scientific evaluations have been conducted to assess the impact of screening programs; therefore, much of this chapter focuses on our speculations about possible impacts. For the purpose of evaluating the effectiveness of screening programs, the objectives of screening and the critical assumptions underlying these objectives are assessed. A primary focus of this chapter is what happens to companies when drug screening programs are initiated. Because screening programs can be implemented in a number of different ways, the answer is largely dependent on the type of program and how it is implemented. These variations in types of screening programs and their possible differential impacts are explored. Prior to exploring these issues, an examination of the history and extent of drug testing programs is provided. This historical perspective is useful for understanding why these programs were initiated and how prevalent they are today.

Factors associated with attitudes toward harm reduction among judges in Ontario, Canada

Abstract Responses from a questionnaire on knowledge and attitudes toward drugs were received from 89 criminal court judges in Ontario, Canada. Younger judges and females were significantly more likely ( P

Drug testing and mandatory treatment for welfare recipients

Abstract One province in Canada, Ontario, is considering the use of drug tests for welfare recipients. Those with positive tests could be required to receive treatment and abstain from drug use or risk losing their benefits. Several experts from the Centre for Addiction and Mental Health (CAMH) reviewed the scientific strengths and weaknesses of this proposal. Strengths included possible increases in employment and reduced drug use among welfare recipients; however, the group concluded that drug testing of welfare recipients or removal of welfare benefits for people who refuse treatment or relapse is not advisable for several reasons. Drug testing cannot be used to determine substance abuse or dependence, could undermine the client case manager relationship and could be legally challenged as a violation of human rights. Other drawbacks of conditional welfare include possible negative societal consequences (i.e. increased crime and health problems) and disruptions to the treatment population. The whole process is expensive and will likely result in a very marginal increase in employment because drug dependence is not a major barrier to employment.

Factors related to self-reported violent and accidental injuries

The main objective of this study is to gain a better understanding of factors that distinguish violent and accidental injuries. A secondary analysis was conducted on data from a randomized telephone survey of 10 385 Canadian residents. Three groups were compared using chi-square tests and logistic regression analyses: respondents who reported no injuries in the previous year, those with at least one accidental injury and those with at least one violent injury. In the bivariate analyses, the violent injury group was significantly more likely than the accidental injury and non-injury groups to be single, widowed, separated or divorced, have more than five drinks on a usual drinking occasion, experience harmful effects of alcohol and to have used illicit drugs, such as cocaine and marijuana, and licit drugs, such as antidepressants and sleeping pills. Finally, the violent injury group was significantly more likely than those with non-violent injuries to report that the incident was related to either their own or someone elses alcohol or drug use. In the final multiple logistic regression analysis, variables significantly associated with injuries due to criminal victimizations compared with accidental injuries were being female, single, cocaine use of the injured and substance use of someone else during the injury.

Judicial attitudes in assault cases involving alcohol or other drugs

The presence or absence of alcohol or other drugs in the commission of crimes can affect sentencing. In order to study this issue, self-administered questionnaires were mailed to all Criminal Division judges in Ontario, Canada. The questionnaire contained questions on both attitudes and sentencing practices for violent crimes where drugs or alcohol were involved. Judges were randomly assigned to four groups and asked to give sentences to hypothetical cases with varying conditions of alcohol and drug involvement. No significant differences were found in terms of severity of sentences for the different conditions; however, the judges said they were more likely to give severe sentences for crimes involving alcohol or other drugs compared to the same crimes when alcohol or other drugs were not involved. For offenders with an alcohol or drug problem, seeking treatment was significantly more likely than not seeking treatment to be viewed as a mitigating factor for sentencing.