Characteristics of teens-with-teens fatal crashes in the United States, 2005–2010

BackgroundMore than 40% of fatal crashes of 16- and 17-year-old drivers occur when transporting teenagers. Characteristics of this predominant crash type and prevention possibilities are described, based on data from fatal crashes in the United States during 2005–2010.ResultsFifty-seven percent of 16- and 17-year old drivers in fatal crashes had at least one passenger. Most commonly, all passengers were ages 13–19 (42% of all drivers and 73% of those with passengers). Of fatal crashinvolved drivers with teenage passengers and no passengers of other ages, 56% had one passenger, 24% had two, and 20% had three or more. Most frequently, passengers were the same sex and within one year of the driver. Risk factors involving speeding, alcohol use, late-night driving, lack of a valid license, seat belt non-use, and crash responsibility were more prevalent with teenage passengers than when driving alone, and the prevalence of these factors increased with the number of teenage passengers. Many risk factors were most prevalent with passengers ages 20–29, although few crashes had this occupant configuration. Risk factors were least prevalent with a passenger 30 or older.DiscussionFatal crashes of 16- and 17-year-old drivers with teen passengers are a common crash scenario, despite passenger restrictions in 42 states and the District of Columbia during some or all of the study period. The proportion of these fatal crashes decreased slightly from 46% in 1995 (pre-GDL) to 43% in 2010 and showed no signs of decreasing during the six-year study period (range 41% to 43%).Practical applicationsExisting passenger restrictions are relatively weak and could be strengthened. Fatal crashes involving teen passengers, especially multiple passengers, are more likely to involve alcohol, late-night driving, driver error, and invalid licensure, so stepped-up enforcement of existing laws involving these behaviors might reduce the prevalence of such crashes.     

The relationship between blood alcohol concentration (BAC), age, and crash risk

PROBLEM: The role of age (youth and driving inexperience) and alcohol as major risk factors in traffic crash causation has been firmly established by numerous studies over the past 50 years. Less well established is how the two variables interrelate to influence crash risk. Some investigations have hypothesized an interactive or synergistic effect in which young drivers with less experience and a greater tendency to take risks are more adversely affected at lower blood alcohol concentrations (BACs) than are older drivers. The evidence for this hypothesis is mixed. Resolution of this issue has important implication for developing countermeasures directed at the young driver crash problem. METHOD: Case control data previously collected in Long Beach and Fort Lauderdale were reanalyzed using a more sensitive method for detecting interaction effects than used in the original analysis. A conditional logistic regression analyses found a highly significant agexBAC interaction (P<.0001) involving differences between drivers under 21 and those 21 and older. DISCUSSION: The results clearly indicate that positive BACs in drivers under 21 are associated with higher relative crash risks than would be predicted from the additive effect of BAC and age. It is likely that two mechanisms are operating to cause the interaction. First, it seems likely that the crash avoidance skill of young novice drivers would be more adversely affected by alcohol due to their driving inexperience, immaturity, and less experience with alcohol. Second, drivers under 21 who choose to drink and to drive after drinking probably have pre-existing characteristics that predisposed them to risk taking and crash involvement apart from any increased vulnerability to alcohol impairment. IMPACT ON INDUSTRY: The results support increased enforcement of zero-tolerance BAC laws for minors.     

Effectiveness of lowering the blood alcohol concentration (BAC) limit for driving from 0.10 to 0.08 grams per deciliter in the United States

Objective: The current study evaluates of the effects of lowering the blood alcohol concentration (BAC) limit from 0.10 to 0.08?g/dL across all 50 states in the United States. Our objectives were to (1) estimate the effects of the 0.08?g/dL BAC limit on drinking driver fatal crash rates; (2) compare the effects from early-adopting states to the effects of late-adopting states; (3) determine the effects on drivers with low BACs (0.01–0.07?g/dL) and high BACs (0.08+ g/dL); and (4) estimate the lives saved since 1983 due to the adoption of 0.08?g/dL BAC laws.

Methods: Our study examined annual data from the Fatality Analysis Reporting System (FARS) for each jurisdiction from 1982 through 2014. Our basic outcome measure was the ratio of drinking drivers (BAC ≥0.01?g/dL) to nondrinking drivers (BAC?=?0.00?g/dL). Covariates included 0.10 BAC laws, administrative license revocation (ALR) laws, seat belt laws, minimum legal drinking age (MLDA) laws, and unemployment rates. We utilized autoregressive integrated moving average (ARIMA) models for each state, where the implementation date of the law was modeled as a zero-order transfer function in the series, in addition to any extant trends that may have been occurring simultaneously. Before determining the specific impact of the implementation of 0.08?g/dL BAC laws, we conducted a time series analysis for each state. We tested for between-state mediating factors relating to our covariates.

Results: A total of 38 of the 51 jurisdictions showed that lowering the BAC limit was associated with reduced drinking driver fatal crash ratios, with 20 of those reductions being significant. The total effects showed a 10.4% reduction in annual drinking driver fatal crash rates, which is estimated to have saved an average of 1,736 lives each year between 1983 and 2014 and 24,868 lives in total. Implementing a BAC limit of 0.08?g/dL had significant impacts on both high- and low-BAC fatal crash ratios. Though early-adopting jurisdictions (1983–1999) demonstrated a larger decrease in fatal drinking driver crash ratios than did late-adopting jurisdictions (2000–2005), the results were not statistically significant (P?>?.05).

Conclusions: Our study of the effects of lowering the BAC from 0.10 to 0.08?g/dL in the United States from 1982 to 2014 showed an overall effect of 10.4% on annual drinking driver fatal crash rates, in line with other multistate studies. This research provides strong evidence of the relationship between lowering the BAC limit for driving and the general deterrent effect on impaired-driving fatal crash rates.     

Spatial relationships between alcohol outlet densities and drunk driving crashes: An empirical study of Tianjin in China

Introduction: Numerous studies have demonstrated the close relationship between alcohol availability and alcohol-related crashes. However, there is still a lack of spatial empirical analysis regarding this relationship, particularly in large cities of developing countries. Differences in alcohol outlets and drinking patterns in these cities may lead to quite different patterns of crash outcomes. Method: 3356 alcohol-related crashes were collected from the blood-alcohol test report of a forensic institution in Tianjin, China. Density of alcohol outlets such as retail locations, entertainment venues, restaurants, hotels, and companies were extracted based on 2114 Traffic Analysis Zones (TAZ) together with the residential and demographic characteristics. After applying the exploratory spatial data analysis, this research developed and compared the traditional Ordinary Least Square model (OLS), Spatial Lag Model (SLM), Spatial Error Model (SEM) and Spatial Durbin Model (SDM) to explore spatial effects of all the variables. Results: The results of incremental spatial autocorrelation show that the most significant distance threshold of alcohol-related roadway traffic crashes is 3 km. The SDM is found to be the optimal spatial model to characterize the relationship between alcohol outlets and crashes. The number of alcohol-involved traffic crashes is positively related to population density and retail density, but negatively related to the company density, hotel density, and residential density within the same TAZ. Meanwhile, dense population and hotels have reverse spillover effects in adjacent zones. Conclusions: The significant spatial direct effect and spillover effect of alcohol outlet densities on drunk driving crashes should not be neglected. These findings could help improve transportation planning, traffic law enforcement and traffic management for large cities in developing countries.     

Epidemiology of alcohol and drug screening among pedestrian fatalities in the United States, 2014–2016

Objective: U.S. pedestrian fatalities increased by 25% between 2010 and 2015. Risk factors include distractions, the built environment, urbanization, economic variables, and weather conditions. Of interest is the role of alcohol and drugs in premature death among pedestrians. This study sought to explore the prevalence of substance use screenings among pedestrian fatalities in the United States between 2014 and 2016.

Methods: Data were collected from the Fatality Analysis Reporting System provided by the NHTSA. Pedestrian crash variables included demographics as well as information regarding alcohol or drug testing status. Frequency and cross-tabulation tables were constructed to assess the prevalence of screening by person, place, and time. Log-linear analyses were completed to explore age, race, and sex differences. A 3-year examination period was used to control for yearly fluctuations and to incorporate an increasing trend in cases.

Results: Pedestrian fatalities accounted for 84% of all deaths among vulnerable road users during the examination period. Those most at risk were white males between the ages of 45 and 64. Over all states, 74.7% of fatalities were tested for alcohol and 67.1% were tested for drugs; further, 66.5% of cases were tested for both alcohol and drugs and 24.8% were tested for neither substance. Cases screened for both alcohol and drugs ranged from 2.9% in North Carolina to 95.7% in Nevada and those testing for neither substance ranged from a high of 68.9% in Indiana to a low of 1.1% in Maryland. Log-linear regression revealed significant differences in alcohol screening by age and race but not by sex. Differences in drug screening were not identified for any demographic variable. Fatalities tested for alcohol were significantly more likely to be tested for drugs; only 8.2% were screened solely for alcohol and 0.05% were screened for drugs alone.

Conclusions: Preventive strategies become more important as pedestrian crashes and fatalities increase. Risk reduction in the form of policy change, alterations to the built environment, or interdisciplinary approaches to injury prevention is dependent upon best evidence supported in part by more deliberate and consistent screening.     

Age,period, and cohort effects in motor vehicle mortality in the United States, 1980–2010: The role of sex,alcohol involvement,and position in vehicle

IntroductionAlthough substantive declines in motor vehicle fatalities in 1980–2010 have been observed, declines by position in the vehicle and alcohol involvement have not been well elucidated.MethodAnalyses of FARS data use the Intrinsic Estimator (IE) to produce estimates of all age, period, and cohort effects simultaneously by position in the car and by alcohol involvement.ResultsDeclines in MVC deaths by position in the car vary for men and women by age and cohort over time. Cohorts born before 1970 had higher risks than those born later. Analyses using proxy indicators of alcohol involvement found the highest risks for those aged 16–24. By period, these risks declined more rapidly than non- alcohol related traffic fatalities.ConclusionChanges in risk patterns are consistent with evidence regarding the contributions of new technologies and public policy efforts to reduce fatalities, but gains have not been shared evenly by sex or position in the car.Practical applicationsGreater attention is needed in reducing deaths among older drivers and pedestrians. Gender differences should be addressed in prevention efforts aimed at reducing MVCs due to alcohol involvement.     

Blood alcohol concentration in fatally injured drivers and the efficacy of alcohol policies of the new law on road traffic safety: A retrospective 10-year study in autonomous province of Vojvodina,Republic of Serbia

Objective: The aim of this study was primarily to evaluate inebriated fatally injured drivers (FIDs) according to blood alcohol concentration (BAC) in a 10-year period (2004–2013) in Autonomous Province (AP) of Vojvodina, Republic of Serbia, to analyze the efficacy of alcohol polices in the new law on road traffic safety through changes in the number of inebriated FIDs before and after implementation of the law, as well as to identify factors that influence the occurrence of FIDs with BACs above the legal limit.

Methods: All data for this retrospective study were obtained from the Centre of Forensic Medicine, Toxicology and Molecular Genetics of Clinical Centre of Vojvodina, Novi Sad. Autopsy records for each case included age, gender, BAC, type of vehicle, and date of accident (year, month, and recalculated day of the week). BAC was determined by gas chromatography with flame ionization detection. Statistical analysis was carried out by chi-square tests and Student's t test, with P < .05 as a statistical significance, and multiple binary logistic regression.

Results: Of the 354 inebriated FIDs (60% of all FIDs), the majority had BACs between of 0.031 and 0.3 mg/ml (28%), followed by those with BAC > 2.01 mg/ml (23%). The average BAC of those driving under the influence of alcohol (DUIA) for the whole period was 1.235 ± 1.00 mg/ml and the average number of DUIA/year was 35. Among the total number of FIDs there were significantly more males (93.7%; P < .001) than females (6.3%), though the distribution of intoxicated men and women was not different (P > .05). There was a statistically significant difference in the distribution of sober and inebriated FIDs according to age (P < .001) with the predominance of inebriated FIDs between 21 and 30 years. Although gender and age were found to be significant predictors of BAC above legal limit in FIDs, the area under the receiver operating characteristics (ROC) curve showed that the model had poor discrimination (ROC = 0.673). Of all observed FIDs, 65 cases per year were attributed to the first 5-year period (2004–2009) and 49 to the second 5-year (2010–2013) period, which indicates that there was no statistically significant decrease in the number of FIDs after implementation of the new law.

Conclusion: The highest number of intoxicated FIDs during the period in AP Vojvodina were mildly and completely inebriated. In the 4-year post-policy period (2010–2013), the number of FIDs and average BAC levels of inebriated FIDs did not significantly change. The abolition of a permissible BAC should be considered.     

Driving under the influence of alcohol and drugs in the eastern part of Denmark in 2015 and 2016: Abuse patterns and trends

Objectives: The objective of this study was to examine the frequency of psychoactive drugs and alcohol in drivers under suspicion of driving under the influence of drugs and alcohol in 2015 and 2016 in the eastern part of Denmark. The trends in the number of traffic cases sent for drug analysis since 2000 and alcohol analysis since 2011 are also discussed.

Methods: Blood samples from drivers suspected of being under the influence of alcohol and/or medication and/or illicit drugs in 2015 and 2016 were investigated as requested by the police. The blood samples were screened for alcohol and/or tetrahydrocannabinol (THC) alone, for other drugs (covering all drugs, except THC, listed in the Danish list of narcotic drugs), or for THC and other drugs. Age and gender were also recorded. The number of drug traffic cases since 2000 and the number of alcohol cases since 2011 were extracted from our Laboratory Information Management System (LIMS).

Results: In total, 11,493 traffic cases were investigated. Alcohol and/or drugs exceeded the legal limit in 9,657 (84%) cases. Men constituted 95% of the drivers investigated for drugs and 88% of the alcohol cases. The drivers investigated for drugs consisted primarily of young men, whereas drivers investigated for alcohol were older.

The frequency was higher for positive alcohol cases above the legal limit (87%) than for drug cases (76%) above the fixed concentration limit. THC (67–69%) was the most frequently detected drug above the legal limit, followed by cocaine (27–28.5%), amphetamine (17%), and clonazepam (6–7%) in both years. Morphine (5.4%), included among the 5 most frequent drugs in 2015, was replaced by methadone (4.6%) in 2016. Few new psychoactive drugs (NPS) were detected.

The number of traffic cases sent for drug analysis has increased more than 30-fold since 2000–2006, and the number of traffic cases submitted in 2016 for drug analysis was higher than the number for alcohol analysis; the latter has decreased since 2011.

Conclusion: Overall, alcohol was the most frequent compound detected above the legal limit in both years, followed by the well-known illicit drugs THC, cocaine, and amphetamine. NPS were seldom seen. One consequence of the increased focus on drugs in traffic has been an immense increase in drug traffic cases sent for analysis since 2006 in the eastern part of Denmark. Although this survey revealed only minimal changes compared to earlier investigations, surveys like this are invaluable for monitoring abuse patterns and trends in drugged and drunken driving.     

Use of child safety seats and booster seats in the United States: A comparison of parent/caregiver-reported and observed use estimates

Background: Motor-vehicles crashes are a leading cause of death among children. Age- and size-appropriate restraint use can prevent crash injuries and deaths among children. Strategies to increase child restraint use should be informed by reliable estimates of restraint use practices. Objective: Compare parent/caregiver-reported and observed child restraint use estimates from the FallStyles and Estilos surveys with the National Survey of the Use of Booster Seats (NSUBS). Methods: Estimates of child restraint use from two online, cross-sectional surveys—FallStyles, a survey of U.S. adults, and Estilos, a survey of U.S. Hispanic adults—were compared with observed data collected in NSUBS. Parents/caregivers of children aged ≤ 12 years were asked about the child’s restraint use behaviors in FallStyles and Estilos, while restraint use was observed in NSUBS. Age-appropriate restraint use was defined as rear-facing child safety seat (CSS) use for children aged 0–4 years, forward-facing CSS use for children aged 2–7 years, booster seat use for children aged 5–12 years, and seat belt use for children aged 9–12 years. Age-appropriate restraint users are described by demographic characteristics and seat row, with weighted prevalence and corresponding 95% confidence intervals (CI) calculated. Results: Overall, child restraint use as reported by parents/caregivers was 90.8% (CI: 87.5–94.1) (FallStyles) and 89.4% (CI: 85.5–93.4) for observed use (NSUBS). Among Hispanic children, reported restraint use was 82.6% (CI: 73.9–91.3) (Estilos) and 84.4% (CI: 79.0–88.6) for observed use (NSUBS, Hispanic children only). For age-appropriate restraint use, estimates ranged from 74.3% (CI: 69.7–79.0) (FallStyles) to 59.7% (CI: 55.0–64.4) (NSUBS), and for Hispanic children, from 71.5% (CI: 62.1–81.0) (Estilos) to 57.2% (CI: 51.2–63.2) (NSUBS, Hispanic children only). Conclusion and Practical Application: Overall estimates of parent/caregiver-reported and observed child restraint use were similar. However, for age-appropriate restraint use, reported use was higher than observed use for most age groups.