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• Attitudes toward driving after cannabis use are predominantly unfavorable. • There is variability in attitudes towards driving after cannabis use across studies. • Attitudes are more favorable among samples of cannabis users. As cannabis policies become more permissive, there is concern that driving after cannabis use (DACU) will increase. From a prevention perspective, understanding whether attitudes toward DACU are positive or negative can guide messaging to reduce DACU. This meta-analysis summarizes quantitative data on attitudes toward DACU safety. Four electronic databases were searched from their inception to February 2024 for studies reporting quantitative data on attitudes toward cannabis use and driving. A total of 1,099 records were retrieved. We summarized data from studies reporting the proportion of respondents endorsing a response option(s) and studies reporting means and standard deviations of endorsed Likert-scale response options using inverse-variance methods. Most respondents had unfavorable views on DACU safety. Among 32 studies, the pooled proportion of respondents endorsing negative attitudes toward DACU was 0.69 (95% CI: 0.62; 0.75). Only ten studies reported the mean and standard deviation of Likert-scale responses; attitudes in these studies were in line with results from the analysis of proportions. Although most people have negative attitudes toward DACU, it is concerning that around one third do not. Prevention initiatives can capitalize on the association between attitude and behaviour to design public messaging. [ABSTRACT FROM AUTHOR]

Background: Driving after cannabis use (DACU) is associated with increased risk of motor vehicle collisions. As cannabis legalization expands, DACU is emerging as a major public safety concern. Attitudes have a significant impact on behavioural decision making. As such, understanding the degree to which people have favorable or unfavorable evaluations of DACU is an important first step for informing prevention efforts. This systematic review summarizes existing evidence on attitudes toward DACU, their association with actual or intended DACU, and changes in attitudes following legalization of recreational cannabis. Methods: Four electronic databases (MEDLINE, EMBASE, PsycINFO, and TRID) were searched for studies that reported attitudes or changes in attitudes toward DACU published between their inception dates and February 26 2024. A total of 1,099 records were retrieved. Studies were analyzed using an inductive thematic synthesis approach. Results: Seventy studies from seven countries originating predominantly from the United States and Canada met inclusion criteria. Thematic analysis identified six themes. (I) Attitudes toward the safety and acceptability of DACU are mixed; participants in 35 studies predominantly expressed negative attitudes toward DACU (e.g., DACU is dangerous, affects driving ability, and increases crash risk). However, 20 studies reported opposing views. (II) Attitudes toward DACU vary by age, sex/gender, and cannabis use frequency; youth, men, and frequent cannabis users tended to view DACU more favorably than older participants, women, and occasional or non-users. (III) Attitudes toward DACU are associated with past DACU and intention to DACU. (IV) DACU is viewed more favorably than driving after drinking alcohol. (V) The relationship between legal status of recreational cannabis and attitudes toward DACU is unclear. (VI) Perceived risk of apprehension for DACU is low to moderate. Conclusions: This review found that perceptions of DACU are primarily negative but mixed. Findings suggest that attitudes toward DACU are important targets for interventions to reduce this behaviour. [ABSTRACT FROM AUTHOR]

Dual use of cannabis and alcohol has increased in adolescents, but limited research has examined how it relates to impaired driving or riding with an impaired driver (IDR) compared to single substance use. This study aimed to examine the odds of alcohol- and/or cannabis-IDR among adolescents based on their use of alcohol and/or cannabis, and whether associations differed by gender and age. Cross-sectional survey data were used from a sample of 69,621 students attending 182 Canadian secondary schools in the 2021/22 school year. Multilevel logistic regression estimated the odds of exclusive alcohol-IDR, exclusive cannabis-IDR, and both alcohol and cannabis IDR (alcohol-cannabis-IDR). Substance use interactions with gender and age were tested. Overall, 14.7% of participants reported IDR; 7.5% reported exclusive alcohol-IDR, 3.2% reported exclusive cannabis-IDR, 4.0% reported alcohol-cannabis-IDR, and 7.4% were unsure if they had experienced IDR. The prevalence of IDR varied across substance use groups, 8.0% among nonuse, 21.9% among alcohol-only use, 35.9% among cannabis-only use, and 49.6% among dual use groups. Gender diverse, older, and students with lower socioeconomic status exhibited a higher likelihood of reporting alcohol-cannabis-IDR. Dual use was significantly associated with 9.5 times higher odds of alcohol-cannabis-IDR compared to alcohol-only use, and 3.0 times higher odds compared to cannabis-only use. Dual use was also associated with an increased likelihood of either alcohol- or cannabis-IDR. This study highlights that all students, regardless of substance use, are at risk of IDR, but students engaged in dual use of alcohol and cannabis face an elevated risk compared to both peers who do not use substances and those who use only a single substance. These findings emphasize the importance of targeted interventions that address the risks associated with IDR. [ABSTRACT FROM AUTHOR]

Abstract Background Driving after cannabis use (DACU) is associated with increased risk of motor vehicle collisions. As cannabis legalization expands, DACU is emerging as a major public safety concern. Attitudes have a significant impact on behavioural decision making. As such, understanding the degree to which people have favorable or unfavorable evaluations of DACU is an important first step for informing prevention efforts. This systematic review summarizes existing evidence on attitudes toward DACU, their association with actual or intended DACU, and changes in attitudes following legalization of recreational cannabis. Methods Four electronic databases (MEDLINE, EMBASE, PsycINFO, and TRID) were searched for studies that reported attitudes or changes in attitudes toward DACU published between their inception dates and February 26 2024. A total of 1,099 records were retrieved. Studies were analyzed using an inductive thematic synthesis approach. Results Seventy studies from seven countries originating predominantly from the United States and Canada met inclusion criteria. Thematic analysis identified six themes. (I) Attitudes toward the safety and acceptability of DACU are mixed; participants in 35 studies predominantly expressed negative attitudes toward DACU (e.g., DACU is dangerous, affects driving ability, and increases crash risk). However, 20 studies reported opposing views. (II) Attitudes toward DACU vary by age, sex/gender, and cannabis use frequency; youth, men, and frequent cannabis users tended to view DACU more favorably than older participants, women, and occasional or non-users. (III) Attitudes toward DACU are associated with past DACU and intention to DACU. (IV) DACU is viewed more favorably than driving after drinking alcohol. (V) The relationship between legal status of recreational cannabis and attitudes toward DACU is unclear. (VI) Perceived risk of apprehension for DACU is low to moderate. Conclusions This review found that perceptions of DACU are primarily negative but mixed. Findings suggest that attitudes toward DACU are important targets for interventions to reduce this behaviour.

The concentration of drugs in a driver's system can change between an impaired driving arrest or crash and the collection of a biological specimen for drug testing. Accordingly, delays in specimen collection can result in the loss of critical information that has the potential to affect impaired driving prosecution. The objectives of the study were: (1) to identify factors that influence the time between impaired-driving violations and specimen collections (time-to-collection) among crash-involved drivers, and (2) to consider how such delays affect measured concentrations of drugs, particularly with respect to common drug per se limits. Study data included blood toxicology results and crash-related information from 8,923 drivers who were involved in crashes and arrested for impaired driving in Wisconsin between 2019 and 2021. Analyses examined how crash timing and severity influenced time-to-collection and the effects of delays in specimen collection on blood alcohol concentrations (BACs) and blood delta-9-tetrahydrocannabinol (THC) concentrations. The mean time-to-collection for the entire sample was 1.80 h. Crash severity had a significant effect on time-to-collection with crashes involving a fatality having the longest duration (M = 2.35 h) followed by injury crashes (M = 2.06 h) and noninjury crashes (M = 1.69 h). Time of day also affected time-to-collection; late night and early morning hours were associated with shorter durations. Both BAC (r = −0.11) and blood THC concentrations (r = −0.16) were significantly negatively correlated with time-to-collection. Crash severity and the time of day at which a crash occurs can result in delays in the collection of blood specimens after impaired driving arrests. Because drugs often continue to be metabolized and eliminated between arrest and biological specimen collection, measured concentrations may not represent the concentrations of drugs that were present at the time of driving. This has the potential to affect drug-impaired driving prosecution, particularly in jurisdictions whose laws specify per se impairment thresholds. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the likelihood of driving after using cannabis, and of being a passenger with someone who is driving after using cannabis, in rural areas and non-rural areas before and after legalization. A multi-wave analysis of Canada's National Cannabis Survey was conducted using logistic regression with interactions to predict the prevalence of driving after using cannabis, and of being a passenger with someone who is driving after using cannabis, in relation to place of residence (rural or non-rural) and in the weeks and months before and after legalization. Three time points were compared: pre-legalization, two months following legalization and 1 year after legalization. At the national level, there are no significant differences between the predicted estimates of driving after using cannabis for those who live in rural and non-rural areas. However, when examining the impact of legalization, we found a significant increase in driving after using cannabis among rural residents directly following legalization. Furthermore, it was observed that this increase in driving after using cannabis returns to pre-legalization rates one year after legalization. By contrast, in the weeks and months following legalization, driving after using cannabis decreased among those living in non-rural areas, and slowly increased soon thereafter. No significant differences were observed, in either time period or group, in the prevalence of being a passenger with someone who is driving after using cannabis. The finding of significantly higher risk of driving after use of cannabis soon after legalization in rural areas suggests a need for more attention to address immediate concerns for public safety. The increased potential for traffic injuries and deaths in other jurisdictions contemplating legalization supports the call for more and better targeted prevention efforts in rural communities that have far too often been overlooked and under-served. [ABSTRACT FROM AUTHOR]

Polydrug use has become a frequent pattern of drug consumption in Europe, and this is considered a particularly dangerous risk factor for impaired driving. In Italy, persons whose license has been revoked or suspended due to the use of psychoactive drugs can reapply for a new driving license, depending on the judgment of the relevant local medical committee (CML). To regain a revoked license, offenders must remain drug free throughout an observation period. An important problem with enforcement of impaired driving is recidivism. The aim of the present study is to analyze the influence of polydrug use on driving recidivism. We report the findings of several years' experience at the forensic toxicology laboratory of the University of Macerata. Hair samples collected over a 7-year period by the CML from drug users were analyzed for cocaine, opiates, and cannabis using gas chromatography–mass spectrometry. Three hundred thirty-five of the tested subjects were recidivists. Recidivism was more frequent among monodrug users (81%) compared with polydrug users (19%), but logistic regression showed that polydrug use is certainly a risk factor for recidivism compared to monodrug use (odds ratio [OR] = 1.99). The sex and age distribution of recidivist subjects showed a strong predominance of males in both groups, but there were no sex differences. There were more recidivist polydrug users than recidivist monodrug users in the younger age groups (OR = 2.012). Cocaine use was most prevalent in the recidivist monodrug group. All drugs analyzed were demonstrated to be a risk factor for recidivism among monodrug users, whereas only the cocaine and cannabis combination was shown to be a risk factor for recidivism among polydrug users (OR = 1.65 versus cocaine; OR = 1.30 versus Δ9-tetrahydrocannabinol). Almost all polydrug users became monodrug users, and cocaine was the most frequently detected drug in the subsequent test during the monitoring phase. Our results show that polydrug use increases the risk of impaired driving recidivism and represents a considerable threat to road safety. [ABSTRACT FROM AUTHOR]

Background: In 2018, Canada legalized recreational use of cannabis and introduced new traffic laws to deter impaired driving. These laws received a significant amount of media coverage during legalization. News media framing of driving after cannabis use (DACU) and related traffic policy can influence public opinion on these issues. Objectives: To understand how DACU and related traffic policy is constructed in Canadian media, examine whether this has changed over time since legalization, and describe and contrast media representation in British Columbia and Ontario. Methods: A database of Canadian news content (Canadian Newsstream) was searched for reports published between January 2017 and December 2021. A total of 261 media reports with a focus on DACU published in English in British Columbia and Ontario were selected. Reports were analyzed using content and thematic analyses. Results: The majority of reports depicted DACU as dangerous and legal changes were typically framed in terms of preventing impaired driving. Concerns were frequently expressed over the reliability and accuracy of roadside oral fluid testing and police readiness to detect impaired drivers. Media description of the effects of cannabis legalization on DACU became more positive after legalization. Media portrayal did not differ markedly between British Columbia and Ontario. Conclusions: Media coverage of the new laws may have enhanced their deterrent effect by informing the public about safety risks and legal repercussions associated with DACU. However, mixed messages about law enforcements’ ability to detect and punish impaired drivers may have encouraged DACU by signalling the uncertainty of punishment.

• TPB is an effective theory at explaining drink driving intentions (DDI) • The relationship between deterrence theory and DDI is ambiguous. • Personal and psychological differences are under-researched areas. • Current theories need to be standardised and better contextualised. • An integrative and more comprehensive approach to deterrence is suggested. Drink driving is a dangerous behaviour that has severe implications for road safety. Despite decades of deterrence initiatives, drink driving remains relatively prevalent, suggesting there may be limitations within current theories used to explain the process of deterrence. In response, this study aimed to perform a systematic review and meta-analysis on what factors are associated with drink driving intentions (DDI). Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, a literature search was performed on six databases. Studies which met the inclusion criteria were correlational by design, contained a variable relating to DDI, and used generalised samples. After an initial screening process, 19 publications met the criteria for the review and 12 for the analyses. The findings showed that the theory of planned behaviour (i.e., attitudes, subjective norms, and behavioural control) sufficiently explained DDI, however, deterrence theory (i.e., risk perceptions), which was notably under-researched, revealed more ambiguous relations to DDI. Experiences with offending and avoidance were also shown to be judicious predictors of DDI, although personal punishment appeared to have a negligible impact, potentially due to the attitude of the offender toward sanctions or the low likelihood of occurrence. The review also highlighted several limitations in the current literature. Firstly, further investigation surrounding the dynamics that underlie risk perceptions of drink-driving is required to reduce the current theoretical ambiguity. Secondly, standardised approaches are needed so that research in this area is more valid and comparable. Finally, researchers may consider operating under an integrated and more comprehensive framework, as there is considerable theoretical overlap between current prominent models of offending, and such approaches will better contextualise individual variables. [ABSTRACT FROM AUTHOR]

Background: Despite women accounting for an increasing proportion of impaired drivers and higher rates of impaired driving and road fatalities in rural areas, little is known about rural women who drive impaired and their other risky behavior. Objective: The present study assessed the association between impaired driving history, risky substance use, and other drug- and sex-related risk behaviors in a sample of high-risk rural women incarcerated in jail. Methods: Four hundred women from three rural jails provided information about their impaired driving, drug use, injection drug use practices, and sex risk behaviors. Groups were stratified on whether they self-reported impaired driving in the year prior to incarceration. Impaired drivers (n = 260, M = 31.90 years old) were compared to women who did not drive impaired (n = 131, M = 34.42 years old) using MANCOVA and logistic regression analyses. Results: Impaired drivers had significantly (p <.05) higher substance use severity scores for cannabis, sedatives, and prescription opioids. Furthermore, impaired drivers were significantly (p <.05) more likely to have been the passenger of an impaired driver (78.08% vs. 53.44%), been an injection drug user (69.62% vs. 41.98%), had a casual sex partner (47.31% vs. 25.95%), and traded sex for drugs or money (31.15% vs. 15.27%) in the year prior to incarceration. Conclusions: This study found a consistent association between past year impaired driving and a range of drug- and sex-related risk behaviors in a sample of high-risk rural women incarcerated in jail. These findings highlight an opportunity to intervene in criminal justice settings to reduce multiple health risk behaviors. [ABSTRACT FROM AUTHOR]

In 2018, Canada became the second country in the world to legalize the use and supply of cannabis for non-medical purposes. The official primary objectives of the government are protecting public health, restricting access by youth, and reducing illicit drug market activity. The mandate of protecting health and safety shifts the focus from justifying punitive responses to addressing increasing rates of use and related risk behaviours such as driving after cannabis use (DACU). To shed more light on DACU through comparison of data immediately before and after legalization in the Canadian experience, we conducted a multi-wave analysis of the National Cannabis Survey. With particular attention to the influence of gender on perceptions and behaviour of youth and young adults, our findings (reassuringly) suggest there have been no measurable increases in self-reported rates of DACU. Whereas gender is a reliably significant predictor, with DACU being far more common among males, we also found that females in this age group are just as likely to report having been as a passenger of a driver who recently used cannabis. The findings are interpreted with reference to research on education and prevention, and gendered variation in peer-based harm reduction initiatives for youth and young adults. [ABSTRACT FROM AUTHOR]

Alcohol- and cannabis-impaired driving behaviors remain a public health concern especially among young adults (i.e., ages 18–25). Limited updates to prevention efforts for these behaviors may be due, in part, to limited understanding of malleable psychosocial predictors. The current study assessed associations between perceived injunctive norms (i.e., acceptability) of driving under the influence of alcohol (DUI-A) and cannabis (DUI-C), and riding with a driver under the influence of alcohol (RWI-A) and cannabis (RWI-C) in Washington State young adults. Participants included 1,941 young adults from the 2019 cohort of the Washington Young Adult Health Survey. Weighted logistic regressions assessed the associations between peer injunctive norms and impaired driving-related behaviors. A weighted total of 11.5% reported DUI-A, 12.4% DUI-C, 10.9% RWI-A, and 20.9% RWI-C at least once in the past 30 days. Overlap between the outcomes was observed, indicating some young adults had engaged in multiple impaired driving-related behaviors. After controlling for substance use frequency, weighted logistic regressions indicated more positive perceived injunctive norms were associated with nearly 2 ½ times higher odds of DUI-A, 8 times higher odds of DUI-C, 4 times higher odds of RWI-A and six and a half times higher odds of RWI-C. Results increase the understanding of how injunctive norms–a potentially malleable psychosocial factor–are associated with four impaired driving-related outcomes. Prevention programs that focus on assessing and addressing the norms of these outcomes individually and collectively, such as normative feedback interventions and media campaigns, may be helpful in reducing these behaviors. [ABSTRACT FROM AUTHOR]

The present study aims to assess the effectiveness of the Drug Evaluation and Classification (DEC) program in Florida. Data from 236 completed DEC evaluations of central nervous system (CNS) depressants, CNS stimulants, narcotic analgesics, and cannabis were analyzed using a classification process comprising toxicology findings and corresponding Drug Recognition Expert (DRE) opinions. A series of standard measures (sensitivity, specificity, false-alarm rate, miss rate, corroboration, and accuracy) were calculated to assess the effectiveness of the DEC program. DREs provided 172 correct opinions and 23 missed opinions, resulting in an accuracy rate of 88%, sensitivity rate of 97%, specificity rate of 23%, false alarm rate of 77%, miss rate of 3%, and corroboration rate of 91%. The 12-step DRE protocol of the DEC program therefore has the desired effect of DREs formulating correct opinions. The specificity and false alarm rate were influenced by the restricted testing procedures in the state of Florida. In general, law enforcement officers certified in the DEC program with specialized training can identify drugged drivers and the correct drug category of the drug causing impairment at the time of operating a vehicle. The DEC program goals are met through rigorous training and a curriculum establishing the 12-step DRE protocol. DRE drug classification opinions identify drugged drivers. The limitations of Florida's biological sample testing procedures have an impact on the specificity of DRE opinions. Addressing these limitations could increase the confirmation rates of the presence of drugs in the individual's biological samples, which would directly impact the conviction rates in DUI-related criminal cases. Further Florida's testing procedures need to be further studied and updated to improve the DEC program in Florida. [ABSTRACT FROM AUTHOR]

Driving under the influence (DUI) is one of the major causes of traffic crashes in Taiwan, leading to huge medical expenditures and human capital loss. Although the authorities have enacted several policies to reduce drunk driving, most penalties are based on drunk drivers' alcohol levels. According to Taiwan regulations, drivers could pay a fine to refuse the breath test if they are not involved in a traffic collision, and there is no clear evidence showing that they are DUI. Therefore, increased sanctions for DUI may lead to increased breath test refusals. If breath tests for drunk driving could be refused with little or no punishments for drivers, then the detection of behavioral impairment would weaken, and the deterrent effect of DUI punishment would be limited. This research uses interrupted time-series analysis (ITSA) to examine how policy reforms from 2007 to 2020 affected driver's breath refusal rate in Taiwan. We find that said reforms that exclusively increase the punishment of DUI offenders did raise the refusal rate immediately and persistently, suggesting that more drunk drivers would refuse a breath test to avoid more severe DUI punishment. Policy reforms that increase penalties for drivers refusing to take breath tests may instantly lower the refusal rate, but the long-term effects are contingent upon the DUI punishment. It appears that drunk drivers could still decide on breath test refusal to avoid a DUI conviction if the punishment for refusing the test is less severe than that for DUI. Aggravating penalties for refusing breath tests would decrease the refusal rate and help reinforce DUI's deterrent effect. [ABSTRACT FROM AUTHOR]

Washington State was among the first states in the US to legalize recreational consumption and retail sales of marijuana. Recreational use of cannabis was legalized December 6, 2012, following the passage of Initiative 502 30 days prior. Roughly 19 months later the first retail cannabis stores opened their doors for public sales ("commercialization"). I measure the impact of cannabis legalization and commercialization on traffic collisions in Washington State. With county-level vehicle crash data from the Washington State Department of Transportation collected monthly, I utilize an interrupted time-series framework with Poisson estimation to compare traffic collisions with recreational retail cannabis sales revenue from 2011 (three years pre-commercialization) through 2017 (three years post-commercialization). First, I measure the shift in collisions brought about by Washington's 2012 cannabis legalization. Then, I compare retail cannabis sales—a measure of commercialization—to traffic collisions based on severity of injury (fatal, severe injury, minor injury, non-injury, and all). After controlling for confounding factors, evidence suggests that recreational cannabis legalization led to fewer fatal and serious injury collisions. Retail cannabis sales generally correlate with more traffic collisions, particularly for less severe (minor injury) crashes. These findings are robust to the inclusion of additional control variables pertaining to county-level cannabis usage and driving behavior while intoxicated. Cannabis legalization led to fewer fatal, serious, and minor injury collisions. Commercialization (cannabis sales) correlated with an increase in less severe crashes. Although cannabis use generally increased in Washington State following legalization/commercialization, survey data suggest that driving behavior while under the influence of cannabis did not change significantly over the post-commercialization period. Future research should focus on measuring the dose-dependent impact of cannabis consumption on traffic collisions. This should include recognition of the importance of cannabis dosing, timing, and route of consumption. Lastly, the dangers of poly-drug driving—particularly cannabis and alcohol—are well established and should be high priority for further research. [ABSTRACT FROM AUTHOR]

Background: Current medical practices and recommendations largely ignore the safety of postconcussion driving, even though commonly used measures of neurocognition, balance, and vestibulo-ocular function show impairment. Purpose: To compare simulated driving between patients with concussion and controls throughout concussion recovery using a case-control design. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 26 concussed and 23 control Division I collegiate athletes completed a driving simulation assessment at 3 time points (within 72 hours, asymptomatic, and return to sport). Cumulative driving simulation outcome variables included total number of collisions, speed exceedances, stop signs missed, lane excursions, total drive time, percentage of time over the speed limit, and percentage of time out of the lane. The mean speed, standard deviation of speed (SDS), lateral lane position, and standard deviation of lateral lane position (SDLP) were examined for each of the 11 drive segments. Outcomes were compared using generalized linear mixed models with random intercepts by participant with Poisson or normal distributions. Results: Within 72 hours of injury, the concussion group committed more lane excursions (median difference, 2; P =.003), exhibited greater SDS while avoiding a child pedestrian crossing the road (Cohen d = 0.73; P =.011), drove ~7 inches (~18 cm) closer to the centerline during a residential left curve (d = 0.90; P =.015), and had greater SDLP while navigating around a car crash compared with controls (d = 0.72; P =.016). When asymptomatic, the concussion group committed fewer speed exceedances (median difference, 2; P =.002) and had lower SDLP while navigating through a traffic light compared with controls (d = 0.60; P =.045). No differences were evident at return to sport. Groups did not differ in total collisions at any time point. Conclusion: The concussion group showed more impaired driving patterns within 72 hours of injury, drove more conservatively once asymptomatic, and had similar driving performance at the time they returned fully to sport. Clinicians should consider these findings when discussing driving with patients acutely after concussion. Further research is needed to determine whether on-road collision risk is elevated after concussion. [ABSTRACT FROM AUTHOR]

Abstract Background Alcohol and cannabis are the most commonly used substances among adolescents in the U.S. The consequences related to using both substances together are significantly higher relative to use of either substance alone. Teens’ propensity to engage in risky driving behaviors (e.g., speeding, rapid lane changes, and texting) and their relative inexperience with the timing and duration of cannabis’ effects puts them at heightened risk for experiencing harms related to driving under the influence. Use of alcohol and cannabis peak at age 16, the legal age teens may apply for a provisional driver’s license in some states. Targeting novice teen drivers prior to licensure is thus an ideal time for prevention efforts focused on reducing alcohol and/or cannabis initiation, use, and impaired driving. Methods The current study proposes to evaluate the efficacy of webCHAT among 15.5 to 17-year-old adolescents (n = 150) recruited at driver education programs. WebCHAT is a single session online intervention that aims to prevent alcohol and cannabis use and risky driving behaviors. We will recruit adolescents enrolled in driver education programs, and stratify based on whether they used cannabis and/or alcohol in the past 3 months (60% screening negative and 40% screening positive). All participants will receive usual driver education and half will also receive webCHAT. We will test whether webCHAT in addition to usual driver education reduces alcohol and/or cannabis initiation or use and reduces risky driving attitudes and behaviors (intent to drive after drinking/using, riding as a passenger with someone who drank/used) compared to teens in usual driver education over a 6-month period. We will also explore whether variables such as beliefs and perceived norms serve as explanatory mechanisms for our outcomes. Discussion The study has the potential to promote public welfare by decreasing adolescent initiation and use of cannabis and alcohol and reducing risky driving behaviors that can have substantial monetary, personal, and social costs. The study recruits adolescents who are at risk for substance use as well as those who are not and it is delivered remotely during a teachable moment when adolescents receive driver education. Trial registration This study was registered with ClinicalTrials.gov on July 13, 2021 (NCT04959461). https://clinicaltrials.gov/ct2/show/NCT04959461

• Examined risk perceptions of driving under the influence of cannabis (DUIC) and alcohol (DUIA). • Compared perceptions of non-medical (ie. recreational) to medical or dual-purpose cannabis users. • Medical or dual-purpose users were more likely to agree that DUIC is safer than DUIA. • No difference found in perception that DUIC increases collision risk. • No difference found in perception that risk of police enforcement is higher for DUIA than DUIC. Reduced perception of potential harm resulting from cannabis use is associated with greater risk of driving under the influence of cannabis (DUIC). Understanding risk perceptions of DUIC among subgroups of users will positively inform targeting and content of anti-DUIC driver education and public awareness campaigns. The current study compared DUIC-related risk perceptions among individuals who use cannabis exclusively for non-medical purposes versus those who use cannabis for exclusively medical or for both medical and non-medical purposes (i.e., dual-purpose users). Data were drawn from a regionally stratified cross-sectional general population telephone survey of adults (18 + years) in Ontario, Canada conducted in 2017. Respondents who reported past-year use of cannabis and answered questions regarding DUIC risk perceptions were selected (weighted N = 343). Modified Poisson regression models with robust standard error estimation were conducted for three attitudes: disagree that DUIC increases motor vehicle collision risk, agree that DUIC is safer than driving under the influence of alcohol (DUIA), agree that chances of being caught by police for DUIA higher than DUIC. In addition to type of cannabis user (non-medical only versus medical or dual-purpose), covariates included demographic characteristics and past-year alcohol and cannabis use frequency. Adjusting for other covariates, regression analyses indicated that medical or dual-purpose cannabis users were 45 % more likely than non-medical users to agree that DUIC is safer than DUIA (Adjusted Prevalence Ratio = 1.45, 95 %CI = 1.10, 1.91, p = 0.007). No other differences in risk perception between medical or dual-purpose and non-medical cannabis users were found. Although no difference between medical or dual-purpose and non-medical cannabis users was found in perceptions of collision risk associated with DUIC or risk of police enforcement, the perception that DUIC is safer than DUIA was stronger among medical or dual-purpose than non-medical users. Recognizing that the shift in public perception of DUIA as a high-risk behaviour contributed to reductions in incidence of DUIA, results of the current study support education and awareness campaigns that target medical or dual-purpose users and emphasize that, like DUIA, DUIC is also a high-risk behaviour. [ABSTRACT FROM AUTHOR]

Driving under the influence of alcohol is one of the greatest dangers to the safety of road users not only in Germany, but across the rest of the world. An essential indicator for both punitive and corrective measures as well as for the prediction of recidivism is the blood alcohol concentration (BAC). This paper examines the relationships between BAC of first-time offenders, former drinking history, traffic related alcohol problem (TRAP), and the outcome of a medical-psychological assessment. The concept of TRAP combines syndromes from Alcohol Use Disorders (AUD) and a non-clinical delinquency category (drink and drive issue without AUD). It is in use for diagnostics among "hard core" alcohol-impaired offenders according to a diagnostic model which is applied in Germany and accepted by the legislator. The present study (N = 505) showed that a BAC of 0.11% upwards must be considered as a risk parameter for the identification of drivers with non-normative, and therefore traffic safety impairing drinking patterns. The importance of BAC as a risk indicator for road safety is underlined by significant correlations between BAC with drinking history and TRAP, but its prognostic value is poor, since BAC was unrelated to the outcome of the medical-psychological assessment. It could be demonstrated that TRAP severity increases with higher age, higher BAC, greater number of drinking days, higher occasion-related drinking amounts, and non-social drinking motivation (against stress and tension). Practical consequences are drawn regarding preconditions for re-issuing a driving licence.

Past research indicates that driving after cannabis use is relatively common. However, not all cannabis users are equally likely to drive after use; frequent cannabis users and frequent drivers are most at risk. It has been suggested that this is due to a perceived lack of impact of cannabis on driving ability. The current study sought to better understand the motivation to drive after recent cannabis use. A survey was used to examine the self-reported impact of cannabis use on driving ability and, further, the amount of time cannabis users wait before driving after use. A total of 562 participants were recruited. Of these, 424 completed the survey and were included for analysis. Purposive sampling was used to screen for cannabis users who were over the age of 18 and residents of Connecticut. Cannabis use frequency was found to predict the self-reported impact of both recreational and medicinal cannabis on driving ability, such that more frequent cannabis users reported less impairment. Additionally, cannabis use frequency was predictive of wait time before driving, where more frequent users reported waiting less time before driving after cannabis use. A plurality of participants reported not waiting at all before driving after using cannabis. Notably, the self-reported impact of cannabis on driving ability was not associated with wait time before driving. Cannabis users may not wait before driving even if they think it has a negative impact on their driving ability. Other factors that potentially impact driving after using cannabis warrant investigation. [ABSTRACT FROM AUTHOR]

Background: Alcohol and cannabis are the most commonly used substances among adolescents in the U.S. The consequences related to using both substances together are significantly higher relative to use of either substance alone. Teens' propensity to engage in risky driving behaviors (e.g., speeding, rapid lane changes, and texting) and their relative inexperience with the timing and duration of cannabis' effects puts them at heightened risk for experiencing harms related to driving under the influence. Use of alcohol and cannabis peak at age 16, the legal age teens may apply for a provisional driver's license in some states. Targeting novice teen drivers prior to licensure is thus an ideal time for prevention efforts focused on reducing alcohol and/or cannabis initiation, use, and impaired driving. Methods: The current study proposes to evaluate the efficacy of webCHAT among 15.5 to 17-year-old adolescents (n = 150) recruited at driver education programs. WebCHAT is a single session online intervention that aims to prevent alcohol and cannabis use and risky driving behaviors. We will recruit adolescents enrolled in driver education programs, and stratify based on whether they used cannabis and/or alcohol in the past 3 months (60% screening negative and 40% screening positive). All participants will receive usual driver education and half will also receive webCHAT. We will test whether webCHAT in addition to usual driver education reduces alcohol and/or cannabis initiation or use and reduces risky driving attitudes and behaviors (intent to drive after drinking/using, riding as a passenger with someone who drank/used) compared to teens in usual driver education over a 6-month period. We will also explore whether variables such as beliefs and perceived norms serve as explanatory mechanisms for our outcomes. Discussion: The study has the potential to promote public welfare by decreasing adolescent initiation and use of cannabis and alcohol and reducing risky driving behaviors that can have substantial monetary, personal, and social costs. The study recruits adolescents who are at risk for substance use as well as those who are not and it is delivered remotely during a teachable moment when adolescents receive driver education. Trial registration This study was registered with ClinicalTrials.gov on July 13, 2021 (NCT04959461). https://clinicaltrials.gov/ct2/show/NCT04959461 [ABSTRACT FROM AUTHOR]

As more countries legalize recreational cannabis, roadside screening programs are imperative to detect and deter driving under the influence of cannabis. This systematic review evaluated roadside screening tests for cannabis use. We searched six databases (inception-March 2020) and grey literature sources for primary studies evaluating test characteristics of roadside screening tests for cannabis use compared to laboratory tests for cannabinoids in blood or oral fluid. The synthesis was focused on sensitivity and specificity of delta-9-tetrahydrocannabinol (THC) detection. 101 studies were included. Oral fluid tests were higher in specificity and lower in sensitivity compared to urine tests when evaluated against blood laboratory tests. Oral fluid tests were higher in sensitivity and similar in specificity compared to observational tests when evaluated against blood and oral fluid laboratory tests. Sensitivity was variable among oral fluid tests; two instrumented immunoassays (Draeger DrugTest 5000 [5 ng/mL THC cut-off] and Alere DDS 2 Mobile Test System) appeared to perform best, but definitive conclusions could not be drawn due to imprecise estimates. Specificities were similar. Overall, oral fluid tests showed the most promise for use in roadside screening for blood THC levels over legal limits; their continued development and testing are warranted. Urine tests are generally inadvisable, and observational tests require sensitivity improvements.

• A fifth of alcohol-impaired Iowa motorcyclists involved in crashes were not charged. • Nearly-one-third of alcohol-impaired drivers did not receive alcohol charges. • Among motorcyclists with an alcohol charge, 87% had an alcohol-related conviction. • Drivers charged with more than one offense type were more likely to be convicted. • Having multiple charge types did not result in higher alcohol-specific convictions. Introduction: Motorcycle fatality rates are increasing, and impaired driving is a major contributing factor. Impaired driving laws are a main component of state efforts to reduce drunk driving, but motorcycle crash charge and conviction outcomes have yet to be studied. The purpose of this study was to evaluate driver charge and conviction outcomes following alcohol-related motorcycle crashes. Methods: Data for this study were drawn from Iowa crash, charge, and conviction data from 2011 to 2018. The study sample included 480 alcohol-influenced drivers (428 motorcyclists and 52 other vehicle drivers) involved in motorcycle crashes. Driver crash-related charges were categorized by type: Alcohol, Moving Violations, and Administrative/Miscellaneous. Factors associated with convictions were determined and estimated with multivariable logistic regression models. The main factor of interest was charge combination. Results: Over three-quarters (78.5%) of the 480 alcohol-influenced drivers in crashes received any charge type and 68.1% received an alcohol-related charge. Among drivers with any charge, 88.6% were convicted, and among drivers with alcohol charges, 87.2% were convicted on an alcohol charge. After adjusting for BAC, drivers with a combination of Alcohol, Administrative, and Moving Violation charges had more than three times the odds of conviction of any charge compared to drivers with alcohol only charges (OR = 3.21, 95% CI = 1.00–10.26). However, charge combinations had little impact on alcohol-related convictions. Conclusions: Convictions were more likely when the impaired driver was charged with multiple types of offenses than with a single offense. An increased variety of charges was not associated with greater rates of conviction on alcohol-specific charges, which had high conviction rates overall. Practical Applications : Law enforcement officers should be informed that lesser infractions impact driver conviction outcomes in alcohol-related crashes and procedures for issuing charges should be evaluated to assure equitable enforcement and to hold drivers accountable for unsafe driving behaviors. [ABSTRACT FROM AUTHOR]

Over the years, road traffic accidents keep claiming lives of people all over the world and alcohol impaired driving is one major cause of these road crashes. While most countries aim at curbing alcohol impaired driving by educating the masses on drunk driving through rallied campaigns, most developed and some developing countries have coupled mass education with technology which includes breathalyzers and ignition interlock devices. This technology has proven to reduce Driving While Intoxicated (DWI) recidivism impressively in countries that have deployed it. This paper aims at proposing a smart vehicle ignition interlock named digiLock to help curb alcohol impaired driving in Ghana and beyond.

Background and aim: In Uruguay, residents age 18 and older seeking legal cannabis must register with the government and choose one of three supply mechanisms: self‐cultivation, non‐profit cannabis clubs or pharmacies. This is the first paper to measure the association between type of legal cannabis supply mechanism and traffic crashes involving injuries. Design Ecological study using ordinary least squares regression to examine how department‐level variation in registrations (overall and by type) is associated with traffic crashes involving injuries. Setting: Uruguay. Cases 532 department‐quarters. Measurements Quarterly cannabis registration counts at the department level and incident‐level traffic crash data were obtained from government agencies. The analyses controlled for department‐level economic and demographic characteristics and, as a robustness check, we included traffic violations involving alcohol for departments reporting this information. Department‐level data on crashes, registrations and alcohol violations were denominated by the number of residents ages 18 and older. Findings From 2013 to 2019, the average number of registrations at the department‐quarter level per 10 000 residents age 18 and older for self‐cultivation, club membership and pharmacy purchasing were 17.7 (SD = 16.8), 3.6 (SD = 8.6), and 25.1 (SD = 50.4), respectively. In our multivariate regression analyses, we did not find a statistically significant association between the total number of registrations and traffic crashes with injuries (β = −0.007; P = 0.398; 95% CI = −0.023, 0.01). Analyses focused on the specific supply mechanisms found a consistent, positive and statistically significant association between the number of individuals registered as self‐cultivators and the number of traffic crashes with injuries (β = 0.194; P = 0.008; 95% CI = 0.058, 0.329). Associations for other supply mechanisms were inconsistent across the various model specifications. Conclusions: In Uruguay, the number of people allowed to self‐cultivate cannabis is positively associated with traffic crashes involving injuries. Individual‐level analyses are needed to assess better the factors underlying this association. [ABSTRACT FROM AUTHOR]

Impaired driving has been a considerable social problem in the U.S. for decades, but efforts to reduce it have stalled after the initial reductions in the 1980's. As a result, legislators continue to develop more polices aimed at deterring impaired driving. Although alcohol has historically been the focus of these efforts, recently there has been increased concern about marijuana impaired driving policies as well. However, alcohol and marijuana impaired driving differ in many ways. This paper explores the costs and benefits of new zero-tolerance policies such as the reduction of the per-se Blood Alcohol Concentration (BAC) level from.08 to.05 for alcohol and the establishment of similar per-se limits for marijuana. These policies are not based on actual impairment and reflect a net widening effect that will criminalize unimpaired drivers, divert criminal justice resources away from the most problematic impaired drivers, and will have little impact on impaired driving crashes. As such, they have the potential to do more harm than good. [ABSTRACT FROM AUTHOR]

Distracted driving is a traffic safety issue worldwide. While the development of comprehensive information and road rules about distracted driving by governments is essential to address the issue, there is evidence showing that existing road rules and information may not always deter drivers from engaging in distractions while driving. Therefore, this study explored drivers' views on government information and road rules concerning distracted driving, aiming to understand how these rules and information have shaped drivers' perceptions and behaviour towards distractions. Interviews (n = 35) were conducted with Queensland drivers aged between 21 and 70 years and a thematic analysis was used to explore the data. Based on the findings, government information on distracted driving was believed by participants to be incomprehensive, not effectively communicated, and focused on mobile phone use. Road rules and enforcement measures often prioritise mobile phone use and contain grey areas that may confuse drivers about legal and illegal distractions. The results showed that the perceived risk of distractions varies among drivers, with some distractions not being considered as risky as other behaviours (e.g., using a smartwatch). Findings showed that government practices are believed to influence drivers' perceptions and behaviour about distracted driving, encouraging an inaccurate perception about driver safety and with the potential to prompt drivers to engage with distracting behaviours without knowledge nor consideration of the risks. The results of this study offer important insights for policymakers in developing and disseminating comprehensive information and road rules for distracted driving., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The designer benzodiazepine bromazolam is increasingly encountered in forensic casework, including impaired driving investigations. A series of suspected impaired driving cases that tested positive for bromazolam are described herein along with information about driving performance, driver appearance and observed behavior. Bromazolam was indicated in casework either through screening by liquid chromatography time of flight mass spectrometry (LC-TOF/MS) and/or a positive benzodiazepine immunoassay screen. Blood samples were forwarded for quantitative confirmatory analysis using a liquid chromatography tandem mass spectrometry (LC-MS/MS) method with a reporting limit of 2.0 ng/mL. Bromazolam was reported in 98 impaired driving cases from samples reported between January 2021 and December 2023, with the earliest detection from September 2020. Mean and median blood concentrations were 125 ± 145 ng/mL and 84 ng/mL respectively, with a range of 4.2 - 990 ng/mL. Additional positive findings were reported in almost all cases, with the highest result (990 ng/mL) being the only case in which bromazolam was the only finding. Fentanyl was the most frequent drug found in combination with bromazolam. Driving behaviors reported in these cases included erratic driving, errors in Standardized Field Sobriety Tests (SFSTs), and symptoms consistent with Central Nervous System (CNS) depressants, including slurred speech, incoordination, and lethargic behavior. Based on its prevalence and demonstrated impairing effects, bromazolam should be included in the scope of impaired driving testing as long as it continues to be prevalent in the drug supply., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site–for further information please contact journals.permissions@oup.com.)

Background and aims: Cannabis and alcohol are frequently detected in fatal and injury motor vehicle crashes. While epidemiological meta‐analyses of cannabis and alcohol have found associations with an increase in crash risk, convergent evidence from driving performance measures is insufficiently quantitatively characterized. Our objectives were to quantify the magnitude of the effect of cannabis and alcohol—alone and in combination—on driving performance and behaviour. Methods: Systematic review and meta‐analysis. We systematically searched Academic Search Complete, CINAHL, Embase, Scopus, Google Scholar, MEDLINE, PsycINFO, SPORTDiscus and TRID. Of the 616 studies that underwent full‐text review, this meta‐analysis represents 57 studies and 1725 participants. We extracted data for hazard response time, lateral position variability, lane deviations or excursions, time out of lane, driving speed, driving speed variability, speed violations, time speeding, headway, headway variability and crashes from experimental driving studies (i.e. driving simulator, closed‐course, on‐road) involving cannabis and/or alcohol administration. We reported meta‐analyses of effect sizes using Hedges' g and r. Results: Cannabis alone was associated with impaired lateral control [e.g. g = 0.331, 95% confidence interval (CI) = 0.212–0.451 for lateral position variability; g = 0.198, 95% CI = 0.001–0.395 for lane excursions) and decreased driving speed (g = –0.176, 95% CI = –0.298 to –0.053]. The combination of cannabis and alcohol was associated with greater driving performance decrements than either drug in isolation [e.g. g = 0.480, 95% CI = 0.096–0.865 for lateral position variability (combination versus alcohol); g = 0.525, 95% CI = 0.049–1.002 for time out of lane (versus alcohol); g = 0.336, 95% CI = 0.036–0.636 for lateral position variability (combination versus cannabis; g = 0.475, 95% CI = 0.002–0.949 for time out of lane (combination versus cannabis)]. Subgroup analyses indicated that the effects of cannabis on driving performance measures were similar to low blood alcohol concentrations. A scarcity of data and study heterogeneity limited the interpretation of some measures. Conclusions: This meta‐analysis indicates that cannabis, like alcohol, impairs driving, and the combination of the two drugs is more detrimental to driving performance than either in isolation. [ABSTRACT FROM AUTHOR]

Abstract Widespread opioid misuse suggests a potential for increased fatal car crashes. However, opioid use may not necessarily lead to additional crashes if drivers respond to opioid prevalence by substituting away from more inebriating intoxicants like alcohol. Combining data on local opioid prescription rates and car crashes from the Fatality Analysis Reporting System, we use two-way fixed-effects models to test the direction of the association between prescribing intensity and crash fatalities between 2007 and 2016. We estimate that a 10 percent increase in the local prescription rate is associated with a 1 percent increase in the number of driver deaths in motor vehicle accidents. The association is robust to several model specifications, and isolated to drivers most affected by the opioid crisis: males and 25- to 34-year-olds. [ABSTRACT FROM AUTHOR]

The Cantonal Police of Zurich, Switzerland, use a checklist to identify impaired drivers when conducting traffic stops. This checklist was developed by subject-matter experts and has been in use for eight years. The goal of this study was to redesign the checklist while considering human factors and ergonomics principles in combination with findings from a retrospective analysis of a set of 593 completed checklists. The checklist was amended in accordance with the results of the retrospective analysis by adding missing items and discarding superfluous ones. In addition, a hierarchical cluster analysis of the retrospective data suggested an improved spatial organization of checklist elements and the grouping of similar items of the checklist. Furthermore, aspects related to Fitts's law, visual complexity, and an optimized direction of processing the checklist underpinned the design process. The results of an evaluation of the redesigned checklist by 11 laypeople and 13 police officers indicated an improved usability of the redesigned checklist over the original. [ABSTRACT FROM AUTHOR]

Driving under the influence of alcohol is one of the greatest dangers to the safety of road users not only in Germany, but across the rest of the world. An essential indicator for both punitive and corrective measures as well as for the prediction of recidivism is the blood alcohol concentration (BAC). This paper examines the relationships between BAC of first-time offenders, former drinking history, traffic related alcohol problem (TRAP), and the outcome of a medical-psychological assessment. The concept of TRAP combines syndromes from Alcohol Use Disorders (AUD) and a non-clinical delinquency category (drink and drive issue without AUD). It is in use for diagnostics among "hard core" alcohol-impaired offenders according to a diagnostic model which is applied in Germany and accepted by the legislator. The present study (N = 505) showed that a BAC of 0.11% upwards must be considered as a risk parameter for the identification of drivers with non-normative, and therefore traffic safety impairing drinking patterns. The importance of BAC as a risk indicator for road safety is underlined by significant correlations between BAC with drinking history and TRAP, but its prognostic value is poor, since BAC was unrelated to the outcome of the medical-psychological assessment. It could be demonstrated that TRAP severity increases with higher age, higher BAC, greater number of drinking days, higher occasion-related drinking amounts, and non-social drinking motivation (against stress and tension). Practical consequences are drawn regarding preconditions for re-issuing a driving licence. [ABSTRACT FROM AUTHOR]

Background Several campaigns on road traffic accidents have been launched by the Federal Road Safety Corps (FRSC) of Nigeria in collaboration with the Beer Sectoral Group (BSG). One such campaign is the "Don't Drink and Drive" intervention launched in 2008. This intervention was initiated to discourage drunk-driving and to improve safety on Nigerian roads through awareness creation. While it is a fact that the the combined enforcement and public education roles of the stakeholders has enormous potentials to tackle drunk driving problems, indigenous empirical evaluation on drivers' exposure and compliance to such DDD messages is scanty. This paper therefore examined motorists' exposure to FRSC's "Don't Drink and Drive" media campaign in South-east, Nigeria and its effects on their compliance levels. Methods A descriptive survey was used to elicit information from 360 registered commercial and private drivers in three selected states (Anambra, Ebonyi and Enugu) in South-eastern region of Nigeria. A multistage sampling approach was adopted in the study. Specifically, a combination of simple random sampling techniques and a purposive sampling procedure was adopted to access respondents across the region under study. Participants volunteered to complete paper version of the questionnaire at their convenience. An independent-samples t-test, a one-way between-groups analysis of variance (ANOVA) and a chi-square test for odd ratio (OR) and relative risks (RR) were performed to test the variables of interests in the study. Results Among other findings, data revealed that in terms of the participants' level of exposure to the DDD campaign, significant differences were observed in age, education, income and number of years spent driving. We also found that drivers' agreement level of the contents of the DDD campaigns was appreciable. Results particularly suggest that the DDD campaigns had a significant impact on drivers' likelihood of avoiding alcohol when driving, reducing alcohol intake at other times and educating others on the danger of drunk driving. Conclusion We conclude that the DDD campaigns might be more effective when policy designers and interventionists concerned with road safety begin to focus on the differences in the demographic characteristics of the drivers. Nonetheless, we advised that the intervention should continue alongside the use of legal back-up (i.e., by imposing some sanctions on drunk drivers) for optimal performance, while campaign efforts should factor in the roles of multiple variables that have been raised in this study.

Motor vehicle crashes are one of the leading causes of death among teenagers. Many of these deaths are due to preventable causes, including impaired and distracted driving. You Drink, You Drive, You Lose (YDYDYL) is a prevention program to educate high school students about the consequences of impaired and distracted driving. YDYDYL was conducted at a public high school in Southern Nevada in March 2020. A secondary data analysis was conducted to compare knowledge and attitudes of previous participants with first-time participants. Independent-samples-t test and χ2 test/Fisher's exact test with post-contingency analysis were used to compare pre-event responses between students who had attended the program one year prior and students who had not. Significance was set at p < 0.05. A total of 349 students participated in the survey and were included for analysis; 177 had attended the program previously (50.7%) and 172 had not (49.3%). The mean age of previous participants and first-time participants was 16.2 (SD ± 1.06 years) and 14.9 (SD ± 0.92 years), respectively. Statistically significant differences in several self-reported baseline behaviors and attitudinal responses were found between the two groups; for example, 47.4% of previous participants compared to 29.4% of first-time participants disagreed that reading text messages only at a stop light was acceptable. Students were also asked how likely they were to intervene if a friend or family member was practicing unsafe driving behaviors; responses were similar between the two groups. The baseline behaviors and attitudes of participants regarding impaired and distracted driving were more protective among previous participants compared to first-time participants, suggesting the program results in long-term positive changes in behaviors and attitudes. The results of this secondary retrospective study may be useful for informing the implementation of future impaired and distracted driving prevention programs. [ABSTRACT FROM AUTHOR]

The government of Washington state legalized recreational cannabis consumption in December 2012. We used data on all drivers involved in fatal crashes in Washington in the years 2008–2019 (n  = 8,282) to estimate prevalence in fatal crashes of drivers with ∆9-tetrahydrocannabinol (THC; the main psychoactive compound in cannabis) in their blood before and after legalization. However, nearly half of the drivers were not tested for drugs; we therefore used multiple imputation to estimate THC presence and concentration among them. We used logistic regression followed by marginal standardization to estimate the adjusted prevalence of THC-positive drivers after legalization relative to what would have been predicted without legalization. In the combined observed and imputed data, the proportion of drivers positive for THC was 9.3% before and 19.1% after legalization (adjusted prevalence ratio: 2.3, 95% confidence interval: 1.3, 4.1). The proportion of drivers with high THC concentrations increased substantially (adjusted prevalence ratio: 4.7, 95% confidence interval: 1.5, 15.1). Some of the increased prevalence of THC-positive drivers might have reflected cannabis use unassociated with driving; however, the increased prevalence of drivers with high THC concentrations suggests an increase in the prevalence of driving shortly after using cannabis. Other jurisdictions should compile quantitative data on drug test results of drivers to enable surveillance and evaluation. [ABSTRACT FROM AUTHOR]

Alcohol-impaired driving results in thousands of deaths annually. Alcohol ignition interlocks require a negative breath test to start a vehicle's engine, and 44 states have mandated some form of interlock law for drivers convicted of driving while intoxicated (DWI). The objective of this study was to estimate the association between interlock laws and fatal impaired-driving crashes. Differences in three interlock laws were evaluated by comparing alcohol-impaired passenger vehicle drivers involved in fatal crashes between 2001 and 2019 in the United States across state and time. State/time differences unrelated to interlock laws were controlled for by fitting a Poisson model. The exposure measure was the number of passenger vehicle drivers in fatal crashes that did not involve impaired drivers. Laws requiring interlocks for drivers convicted of DWI covered: repeat offenders, repeat offenders and high-BAC offenders, all offenders, or none. The number of states with all-offender interlock laws during the study period went from three in 2001 to 29 in 2019, and the number of states with any of the three laws increased from 16 to 44. All-offender laws were associated with 26% fewer drivers with 0.08+ BAC involved in fatal crashes, compared with no law. Repeat-offender laws were associated with a 9% reduction in impaired drivers, compared with no law. Repeat and high-BAC laws were associated with a 20% reduction in impaired drivers in fatal crashes, compared with no law. Laws mandating alcohol ignition interlocks, especially those covering all offenders, are an effective impaired-driving countermeasure that reduces the number of impaired drivers in fatal crashes. [ABSTRACT FROM AUTHOR]

Abstract Background Drug driving is an emerging global road safety problem. As the prevalence of alcohol-impaired driving decreases, and as more jurisdictions decriminalize or legalize cannabis, it is increasingly important for policy makers to have accurate information on the prevalence and pattern of drug driving. Unfortunately, this data is not widely available and the World Health Organization identifies lack of accurate data on the prevalence of drug driving as an important knowledge gap. Methods In this paper, we discuss the limitations of current methods of monitoring drug use in drivers. We then present a novel methodology from a multi-centre study that monitors the prevalence and pattern of drug use in injured drivers across Canada. This study uses “left-over” blood taken as part of routine medical care to quantify cannabis and other drugs in non-fatally injured drivers who present to participating emergency departments after a collision. Toxicology testing is done with waiver of consent as we have procedures that prevent results from being linked to any individual. These methods minimize non-response bias and have the advantages of measuring drug concentrations in blood obtained shortly after a collision. Discussion Our methods can be applied in other jurisdictions and provide a consistent approach to collect data on drug driving. Consistent methods allow comparison of drug driving prevalence from different regions. Data from this research can be used to inform policies designed to prevent driving under the influence of cannabis and other impairing drugs.

• Cannabis use and cannabis-impaired driving are very common among Canadian youth. • We provide survey and focus group data on youth's perceptions on cannabis & driving. • Findings can inform the development of impaired driving preventative efforts. Preventing youth from driving under the influence of cannabis (DUIC) remains a road safety priority. This study aimed to understand beliefs of young Ontarian drivers (ages 18–24) towards cannabis use and DUIC. Using a mixed methods design, we conducted an online survey (n = 426, 53% female) and two focus groups (n = 12, 67% female). The survey obtained data in the following sections: demographics, experiences and expectancies related to cannabis use and DUIC, knowledge and credibility of the law, attitudes towards DUIC, and social controls. Quantitative data was analyzed in SPSS using descriptive statistics and chi squares. Two focus groups were then conducted to contextualize quantitative findings. Audio recordings were transcribed and analyzed using inductive thematic analysis. 83.6% (356) of survey's participants had used cannabis, with 69% (296) in the past year. Among past-year users, 47.9% (142; 33.3% of the sample) reported DUIC. Those who indicated prior history of DUIC were mostly males, had completed less than a bachelor's degree, and were students without employment. Qualitative themes included: Being high changes you; it is hard to tell if a driver is high; DUIC is convenient, socially acceptable, and safe; legalization makes cannabis more attractive to use; and there is a need for testing, education, and prevention efforts that are relevant to youth. A considerable number of young drivers in Ontario are currently DUIC, many of which underestimate the associated risks. Our findings provide insight into youth's beliefs towards DUIC and considerations for preventative efforts. [ABSTRACT FROM AUTHOR]

• Investigates user intention to use autonomous vehicle while impaired. • User intention are primarily dependent on their attitudes and perceptions. • Although generally accepting, users are reluctant to AV use while impaired. In this study, we employ the Integrated Choice Latent Variable (ICLV) framework to model the public's intention of using Autonomous Vehicles (AVs) while impaired under the influence of alcohol, medicine, or fatigue. We identify five latent constructs from psychometric indicators that define respondent's perception and attitudes towards AVs which are i) perceived benefits, ii) perceived risks, iii) enjoy driving, iv) wheels public transport attitude, and v) rails public transport attitude. We use these latent variables along with explanatory variables to study user intentions regarding delegation of vehicle control from human driving to autonomous driving. The study uses survey data collected from 1,065 Czech residents between 2017 and 2018. Our findings indicate that user intentions are primarily defined by attitudes rather than socio-demographic attributes. However, the inclusion of both types of variables is crucial in evaluating user intentions. Despite a positive outlook towards AVs, people were found to be reluctant in using AVs while impaired which can be attributed to distrust towards the technology. Our analysis shows that with appropriate efforts from policymakers, the public's attitude can be changed to promote adoption. The efforts will have to be emphasized towards building positive attitudes (such as perceived benefits) and diminishing existing negative attitudes (such as perceived risks). [ABSTRACT FROM AUTHOR]

Background/Purpose: A growing body of evidence suggests that people who are arrested for driving under the influence (DUI) of alcohol are more likely to screen positive for psychiatric disorders than the general population. Additionally, psychiatric comorbidity has been shown to increase vulnerability to criminal re-offense. However, DUI programs face many barriers to screening for psychiatric disorders. This paper evaluates the sensitivity and specificity of a screening tool developed for these programs, the Computerized Assessment and Referral System (CARS) Screener. Methods: We used data from 381 DUI offenders in Massachusetts, as well as a secondary data source, the National Comorbidity Survey-Replication (NCS-R: N = 9,282) to examine the accuracy of the CARS Screener when compared to full assessment. Results: Based on both sets of analyses, we found that the CARS Screener offers a sensitive and specific method to screen for many psychiatric disorders. Specifically, the CARS Screener has a high sensitivity and specificity for bipolar disorder, intermittent explosive disorder, depressive disorders, generalized anxiety disorder, alcohol and drug use disorders, gambling disorder, post-traumatic stress disorder, panic attacks, and social phobia. Conclusion: The CARS Screener appears to be an effective tool that will help DUI programs better understand and address the mental health issues facing their clients. [ABSTRACT FROM AUTHOR]

Objectives: Evaluate the deterrent effect of a program that increases the certainty and celerity of sanction for arrestees ordered to abstain from alcohol and other drugs on substance-impaired driving arrests. Methods: We examine participant compliance with orders to abstain from alcohol and other drug use via breathalyzer, body-worn continuous alcohol monitoring devices, transdermal drug patches, and urinalyses. We then evaluate the impact of the 24/7 Sobriety program on substance-impaired driving arrests. Using variation across counties in the timing of program implementation in North Dakota as a natural experiment, we use difference-in-differences fixed effects Poisson regressions to measure the program's effect on county-level arrests for substance-impaired driving. Results: Over half of participants ordered to abstain from substance use complete 24/7 Sobriety without a detected substance use event. At the county level, the program is associated with a 9% reduction in substance-impaired driving arrests after accounting for the impact of oil exploration in the Bakken region, law enforcement intensity, alcohol availability, whether the state's large universities were in session, and socio-demographic characteristics. We find that the Bakken oil boom is associated with a 22% increase in substance-impaired driving arrests. Conclusions: The results suggest frequent monitoring combined with increased sanction celerity deters substance use-involved crime. While the results are generally consistent with an earlier study of 24/7 Sobriety in another state, differences in the study outcome measures implementation choices across states make direct comparisons difficult. More can be learned by conducting randomized controlled trials that vary time on program, testing technology, and/or level of sanction. [ABSTRACT FROM AUTHOR]