Alcohol-involved motor vehicle crashes and the size and duration of random breath testing checkpoints

Scheduling optimisation of alcohol test sites

Drink driving is an infamous factor in road crashes and fatalities. Alcohol testing is a major countermeasure, and random breath tests (RBTs) deter tested drivers and passersby (observers who are not tested). We propose a genetic algorithm (GA)-based RBT scheduling optimisation method to achieve maximal deterrence of drink driving. The RBT schedule denotes the daily plan of where, when, and for how long tests should occur in the road network. The test results (positive and negative) and observing drivers are considered in the fitness function. The limited testing resource capacity is modeled by a number of constraints that consider the total duration of tests, the minimum and maximum duration of a single test site, and the total number of test sites during the day. Clustering of the alcohol-related crash data is used to estimate the matrix for drink driving on the scheduled day. The crash data and traffic flow data from Victoria, Australia are analysed and used to describe sober/drink driving. A detailed synthetic example is developed and a significant improvement with 150% more positive results and 59% more overall tests is observed using the proposed scheduling optimisation method.

Driving Under the Influence of Alcohol, Cannabis, and Delta-8 THC: Perceived Likelihood, Risk Perceptions, and Behaviors

Driving under the influence (DUI) of alcohol or cannabis poses public health risks. Little is known about DUI of Delta-8 THC, a newer cannabis product. Using 2022 survey data among 189 U.S. adults ages 18-25 (58.73% male, 59.26% non-Hispanic White), multivariable logistic regression examined substance-specific (alcohol, cannabis, Delta-8) DUI perceived likelihood and risk in relation to past-year DUI among those with past-year use of each. Overall, 72.49% reported past-year alcohol use, 50.53% cannabis, and 22.46% Delta-8. Among those reporting past-year use of each respective substance, 33.58% reported DUI of alcohol, 32.63% cannabis, and 57.14% Delta-8. On average, participants had the same DUI perceived likelihood ("somewhat unlikely") across substances and perceived alcohol DUI as riskiest. Higher alcohol DUI perceived likelihood and lower perceived risk were associated with alcohol-related DUI. Greater cannabis-related perceived likelihood (but not risk) was associated with cannabis-related DUI. Neither Delta-8 DUI perceived likelihood nor risk were associated with Delta-8 DUI. In sum, perceived DUI likelihood for alcohol, cannabis, or Delta-8 tended to be similar. Among those with past-year use of each, the proportion of DUI was highest for Delta-8. Interventions should target DUI-related perceived likelihood and promote protective behavioral strategies that reduce substance-specific DUI risk.

Driving under the influence of cannabis versus alcohol: A mixed-methods study examining perceptions and related risk behaviors among US and Israeli adults

BACKGROUND

Despite the dangers of driving under the influence (DUI), little is known about DUI substance-specific risk perceptions or risk factors for riding with drunk/drugged drivers (RDD).

METHODS

In this sequential exploratory mixed-methods study, we conducted: 1) multivariable analyses of cross-sectional survey data from 2222 US and Israeli adults to identify correlates of perceived cannabis- vs. alcohol-related DUI risks (linear regression) and past-month RDD involving alcohol-only, cannabis-only, or both (alcohol-cannabis) (multinomial logistic regression); and 2) deductive-inductive thematic analyses of qualitative interview data from 84 participants to identify themes elaborating on survey findings regarding DUI-related risk perceptions.

RESULTS

54.0 % reported past-month alcohol use, 16.7 % cannabis use, 4.2 % alcohol-only RDD, 5.5 % cannabis-only RDD, and 7.9 % alcohol-cannabis RDD. Being from the US, not having children at home, and cannabis non-use correlated with lower perceived cannabis vs. alcohol DUI risk. Lower perceived cannabis vs. alcohol DUI risk correlated with cannabis-only and alcohol-cannabis (vs. no) RDD, and with alcohol-cannabis (vs. cannabis-only) RDD. Alcohol use correlated with alcohol-only (vs. no) RDD and alcohol-cannabis (vs. cannabis-only) RDD. Cannabis use correlated with cannabis-only and alcohol-cannabis (vs. no) RDD, and with alcohol-cannabis (vs. alcohol-only) RDD. Being from the US correlated with alcohol-only (vs. alcohol-cannabis and none) RDD and cannabis-only (vs. alcohol-cannabis) RDD; being from Israel correlated with alcohol-cannabis (vs. no) RDD. Qualitative data indicated most participants perceived greater risk of DUI of alcohol vs. cannabis and desired more effective DUI-related prevention and regulatory efforts.

CONCLUSIONS

Prevention interventions targeting DUI- and RDD-related risk perceptions are needed, particularly for high-risk populations.

Dynamic relations among simultaneous alcohol and cannabis use, subjective responses, and problem drinking during naturally occurring drinking episodes

BACKGROUND

Simultaneous alcohol and cannabis use (SAM) is associated with riskier drinking. However, little is known regarding mechanisms of risk during drinking episodes. The current study tested whether subjective responses to simultaneous vs. alcohol-only use (i.e., high arousal positive/reward, high arousal negative/aggression, low arousal positive/relaxation, low arousal negative/impairment) were mechanisms through which SAM use was associated with daily drinking.

METHODS

Emerging adults who co-use alcohol and cannabis (N=85) completed 21 days of ecological momentary assessment with drink-contingent reports during drinking episodes. Participants reported on their simultaneous use and current subjective effects during drink reports and past-night total drinks consumed and negative consequences experienced the next morning. Three-level multilevel models (momentary, daily, person level) tested whether SAM use predicted subjective responses, and whether subjective responses mediated associations between SAM use, heavier drinking and negative consequences.

RESULTS

At the momentary and day-level, SAM (vs. alcohol-only) use predicted increased high arousal positive/rewarding, low arousal positive/relaxing, and low arousal negative/impairing subjective effects. SAM use indirectly predicted heavier day-level drinking and further negative consequences through high arousal positive/rewarding response. SAM use also indirectly predicted day-level negative consequences through low arousal negative/impairing response. At the person-level, more frequent SAM use predicted higher person-average high arousal positive/rewarding and low arousal positive/relaxing responses, and high arousal positive/rewarding response mediated relation between SAM frequency and heavier drinking.

CONCLUSIONS

Simultaneous use was associated with reward, relief, and impairment, and reward and impairment were mechanisms of risk between SAM use and riskier drinking. Findings may inform theory and just-in-time interventions seeking to reduce alcohol misuse.

Optimizing sobriety checkpoints to maximize public health benefits and minimize operational costs

BACKGROUND

Sobriety checkpoints are a highly effective strategy to reduce alcohol-impaired driving, but they are used infrequently in the USA. Recent evidence from observational studies suggests that using optimized sobriety checkpoints-operating for shorter duration with fewer officers-can minimize operational costs without reducing public health benefits. The aim of this research was to conduct a pilot study to test whether police can feasibly implement optimized sobriety checkpoints and whether researchers can examine optimized sobriety checkpoints compared to usual practice within a non-randomized controlled trial study design.

METHODS

The study site was the Town of Apex, NC. We worked with Apex Police Department to develop a schedule of sobriety checkpoints during calendar year 2021 that comprised 2 control checkpoints (conducted according to routine practice) and 4 optimized checkpoints staffed by fewer officers. Our primary operations aim was to test whether police can feasibly implement optimized sobriety checkpoints. Our primary research aim was to identify barriers and facilitators for conducting an intervention study of optimized sobriety checkpoints compared to usual practice. A secondary aim was to assess motorist support for sobriety checkpoints and momentary stress while passing through checkpoints.

RESULTS

Apex PD conducted 5 of the 6 checkpoints and reported similar operational capabilities and results during the optimized checkpoints compared to control checkpoints. For example, a mean of 4 drivers were investigated for possibly driving while impaired at the optimized checkpoints, compared to 2 drivers at control checkpoints. The field team conducted intercept surveys among 112 motorists at 4 of the 6 checkpoints in the trial schedule. The survey response rate was 11% from among 1,045 motorists who passed through these checkpoints. Over 90% of respondents supported sobriety checkpoints, and momentary stress during checkpoints was greater for motorists who reported consuming any alcohol in the last 90 days compared to nondrinkers (OR = 6.7, 95%CI: 1.6, 27.1).

CONCLUSIONS

Results of this study indicate the sobriety checkpoints can feasibly be optimized by municipal police departments, but it will be very difficult to assess the impacts of optimized checkpoints compared to usual practice using an experimental study design.

Unintended reductions in assaults near sobriety checkpoints: A longitudinal spatial analysis

BACKGROUND

Sobriety checkpoints are a form of proactive policing in which law enforcement officers concentrate at a point on the roadway to systematically perform sobriety tests for all passing drivers. We investigated whether sobriety checkpoints unintentionally reduce assaults in surrounding areas.

METHODS

Exposures of interest were sobriety checkpoints conducted by the Los Angeles Police Department between 2012 and 2017. Comparison units were matched 1:2 to sobriety checkpoints, selected as the same point location temporally lagged by exactly ±168 hours. The outcome was the density of police-reported assaults around the checkpoint location.

RESULTS

In mixed effects regression analyses, assault incidence was lower when sobriety checkpoints were in operation compared to the same location ±168 hours [b= -0.0108, 95% CI: (-0.0203, -0.0012)].

CONCLUSIONS

Sobriety checkpoints were associated with decreased assault incidence, but estimated effect sizes were small and effects did not endure long after checkpoints ended.

A study into the nature and extent of drug driving recidivism in Queensland (Australia)

INTRODUCTION

While research has reported on overall prevalence rates of drug driving, the extent of recidivist offending has yet to be explored. The objective of this research was to examine recidivistic behaviors detected through Roadside Drug Testing (RDT) in Queensland (between December 2007 and June 2020), with a focus on: Delta-9-tetrahydrocannabinol (THC), 3,4-Methylenedioxymethylamphetamine (MDMA), and methamphetamine (MA).

METHOD

Data were provided by the Queensland Police Service, and contained information on positive drug detections that were confirmed via laboratory analysis.

RESULTS

The analyses revealed 50,442 unique offenders with a total of 67,727 offenses, as 25% (N = 12,490) of all offenders had been apprehended more than once (ranging from 2 to 11 offences). MA use was more common among recidivist offenders, whereas THC was more common for those with one offense. On average, the days between offenses decreased with increases in offense number.

CONCLUSIONS

The findings provide evidence for the extent of drug driving recidivism on Queensland roads.

PRACTICAL APPLICATIONS

To deter recidivists and the greater motorist population from drug driving, there is need for greater resources dedicated to RDT to increase both the perceived and real likelihood of detection.

The geography of sobriety checkpoints and alcohol-impaired driving

BACKGROUND AND AIMS

Sobriety checkpoints are an effective strategy to reduce alcohol-impaired driving, motor vehicle crashes, injuries and fatalities. The aim of this study was to identify the geographic extent over which individual sobriety checkpoints affect alcohol-impaired driving.

DESIGN, SETTING, PARTICIPANTS

Spatial ecological panel analysis using geolocated breath test data from the Queensland Police Service, Australia, for January 2012 to June 2018. Data were aggregated over 338 weeks within 528 Statistical Area level 2 (SA2) units (n = 178 464 SA2-weeks) and 84 Statistical Area level 3 (SA3) units (n = 28 392 SA3-weeks). SA2 units in Queensland contain a mean population of 8883.5 (SD = 55 018.3) and encompass 468.9 roadway kilometers (SD = 1490.0); SA3 units contain a mean population of 57 201.6 (SD = 29521.6) and encompass 2936.0 roadway kilometers (SD = 7025.0).

MEASUREMENTS

Independent measures were the density of sobriety checkpoints conducted per 500 roadway kilometers within local and spatially adjacent space-time units. The dependent measure was the rate of tests that detected breath alcohol concentration (a proxy for blood alcohol concentration [BAC]) greater than the legal maximum value of 0.05% for fully licensed drivers in Queensland. Bayesian hierarchical spatial negative binomial models-related sobriety checkpoints to the rate of breath tests with BAC ≥ 0.05% within and between space-time units.

FINDINGS

One additional sobriety checkpoint conducted per 500 roadway kilometers was associated with 2.5% reduction in the rate of breath tests with BAC ≥ 0.05% within local SA2 units (incidence rate ratio [IRR] = 0.975; 95% credibility interval (CrI): 0.973-0.978), and with 5.5% reduction in the rate of breath tests with BAC ≥ 0.05% within local SA3 units (IRR = 0.945; 95%CrI: 0.937-0.953). Associations were attenuated towards null in spatially adjacent units and in temporally lagged units (e.g. SA3-weeks; adjacent lagged 1 week: IRR = 0.969; 95%CrI: 0.937-1.003).

CONCLUSIONS

Individual sobriety checkpoints appear to be associated with reductions in nearby alcohol-impaired driving. Relationships decay after approximately 1 week and beyond local areas containing approximately 60 000 residents and 3000 kilometers of roadway.