Driving exposure by driver age in Michigan.

BACKGROUND: This study compared driving exposure between two high-crash-risk groups (16-17 and 18-24-year-olds), with a low-crash-risk group (35-64-year-olds). In addition, patterns of association between driving exposure measures and demographic and driving behavior variables were examined. METHODS: Respondent's total miles, minutes, and trips driven were calculated within a 48-hour period, using state-wide survey data collected in 2004 and 2005. RESULTS: The youngest drivers drove fewer miles and minutes, but a comparable number of trips as the two older groups. Employment and high vehicle access were associated with greater driving exposure for 16-17-year-olds and 18-24-year-olds. Employment, high household income, large household size, and low vehicle access were associated with greater driving exposure for 35-64-year-olds. More driving was done alone than with passengers present and during the day than at night across all ages. There was a positive association between two driving exposure measures (miles and minutes driven) and demographic and driving behavior variables, which did not extend to trips driven. DISCUSSION: Driving exposure is directly related to stage of life. The entire sample of 16-17-year-old respondents were in high school, which directly influenced their driving times, destinations, and purpose. Those aged 18-24years displayed driving behavior patterns that were closer to the older drivers, while retaining some differences. The oldest drivers were likely to be shouldering the greatest household responsibilities, and their greater driving exposure may reflect this reality. IMPACT ON INDUSTRY: These findings provide new information about driving exposure for two high-risk and one low-risk group of drivers. They also raise concern over potential workplace safety issues related to teens' higher driving exposure, and concomitant crash risk, related to being employed. Future research should examine this issue more carefully so that evidence based recommendations can be made to enhance the safety of teens who are employed, especially those who are employed as drivers.

Teen driving exposure in Michigan: demographic and behavioral characteristics.

Motor vehicle crashes are the leading cause of death and a leading cause of non-fatal injury for teenagers in the United States. Understanding teen crashes requires a good measure of crash risk. The measure of exposure that is used in the calculation of risk estimates determines what information the resulting rates and rate ratios provide and the conclusions that can be drawn about teen driver crash risk. The purpose of this study is to provide an initial description of three measures of individual-level exposure to driving for 16-17-year-olds in the state of Michigan, using data from the state-wide Michigan Travel Counts survey conducted in 2004 and 2005. The total miles, minutes, and trips driven within the 48-h survey period were calculated for each respondent using self-reported measures and geo-spatial mapping. Young drivers who worked and those with greater access to a vehicle drove significantly more than their peers who did not work and those who had less access to a vehicle. Those from urban residences spent more time driving than those from rural residences. All 16-17-year-olds drove substantially more during the day than at night, and on their own than with passengers. There was little difference in overall driving exposure and driving behavior between young men and young women. This study provides an initial description of driving exposure and behavior for a population for which there is very little specific information about amounts and patterns of individual driving exposure. The relationship between individual driving exposure and risk of motor vehicle crash, injury or fatality requires further investigation.

Casualty crash types for which teens are at excess risk.

This study identified casualty crash types for which teen drivers experience excess risk relative to adults. Michigan State Police crash records were used to examine casualty crashes in two statewide populations of drivers who experienced at least one crash from 1989-1996 (pre-graduated driver licensing in Michigan): teens (ages 16-19) and adults (ages 45-65). Rates and rate ratios (RR) based on crash occurrence per 100,000 person miles driven (PMD) compared teens and adults from the two statewide populations. Excess risk was defined as a RR for a specific type of crash that was significantly greater than the RR for all crashes combined. The RRs for all crashes combined for teenage males was 2.41 and 1.75 for teenage females. RRs for teenage males ranged from a low of 2.16 for casualty crashes attributed to alcohol to 8.98 for casualty road departure crashes at night. Among teenage females, RRs ranged from 2.06 for casualty crashes on the weekend to 7.86 for casualty crashes at night with passengers. Casualty crash rates for teenage males ranged from 0.21 per 100,000 PMD for rollover crashes to 1.95 per 100,000 PMD for crashes with passengers. Among teen females, casualty crash rates ranged from 0.21 per 100,000 PMD for drink/driving with passengers to 3.31 per 100,000 PMD for crashes with passengers. Implications for graduated driver licensing, teen driver supervision, and policy are discussed. This study was funded by the National Institute on Alcohol Abuse and Alcoholism and the Centers for Disease Control and Prevention's National Center for Injury Prevention and Control.

Influences on youthful driving behavior and their potential for guiding interventions to reduce crashes.

This paper presents an organized, comprehensive view of the factors known to influence young drivers' behavior and how those factors might inform interventions to reduce crashes. This effort was done from the perspective of a public health professional, with a background in health behavior and health education, interested in preventing injury and death among young people from motor vehicle crashes. The author's own studies, selected relevant literature, observation, and experience were considered and organized. A framework of six categories of influences on youthful driving behavior was developed, including the following elements: driving ability, developmental factors, personality factors, demographics, the perceived environment, and the driving environment. It is apparent that a complex set of many different factors influences young drivers' behavior. To reduce crashes, comprehensive, multilevel interventions are needed that target those factors in the framework that are amenable to change.

Graduated driver licensing in Michigan: early impact on motor vehicle crashes among 16-year-old drivers.

CONTEXT: Graduated driver licensing (GDL) programs are being adopted in many states to address the high rate of motor vehicle fatalities among teens by requiring teenaged drivers to gain experience and maturity under conditions of relatively low crash risk before gaining full driving privileges. OBJECTIVE: To evaluate the early impact of Michigan's GDL program on traffic crashes among 16-year-old drivers. DESIGN, SETTING, AND SUBJECTS: Analysis of Michigan motor vehicle crash data from 1996 (before GDL program implementation) vs 1998 and 1999 (after GDL program implementation) for 16-year-olds, adjusting for trends among persons 25 years or older. INTERVENTION: Michigan's GDL program, instituted April 1, 1997, for teens younger than 18 years entering the driver license system, includes 3 licensure levels, each with driving restrictions and requirements to progress to the next level. Requirements include extended, supervised practice in the learning level, 2-phase driver education, and night driving restrictions in the intermediate level. MAIN OUTCOME MEASURES: Rates in 1996 vs 1998 and 1999 for all police-reported crashes; for fatal injury, nonfatal injury, and fatal/nonfatal injury combined crashes; for day, evening, and night crashes; for single-vehicle and multivehicle crashes; and for alcohol-related crashes. RESULTS: Overall, the rate of 16-year-old drivers (per 1000 population) involved in crashes declined from 154 in 1996 to 111 in 1999 (relative risk [RR], 0.72; 95% confidence interval [CI], 0.71-0.73). After adjusting for populationwide trends, the overall crash risk for 16-year-olds was significantly reduced in 1999 from 1996 by 25% (adjusted RR, 0.75; 95% CI, 0.74-0.77). There were also significant reductions for nonfatal injury and combined fatal and nonfatal crashes; for day, evening, and night crashes; and for single-vehicle and multivehicle crashes. Fatal crashes declined from 1996 to 1999, but not significantly (RR, 0.74; 95% CI, 0.49-1.14), and alcohol-related crashes continued at a low rate (RR, 1.01; 95% CI, 0.80-1.29). CONCLUSIONS: Analysis of the first 2 full calendar years following Michigan's GDL program implementation indicates substantial crash reductions among 16-year-olds. Future research is necessary to determine if these reductions are maintained and if other jurisdictions achieve similar results.

Adolescent antecedents of high-risk driving behavior into young adulthood: substance use and parental influences.

Driver history data, in combination with previously collected tenth-grade questionnaire data, for 4403 subjects were analyzed by Poisson regression models to identify the significant substance use and parental characteristics predicting subsequent high-risk driving of new drivers (starting at age 16) through age 23-24 years. Substance use (cigarettes, marijuana, and alcohol) reported at age 15 was shown to be an important predictor of subsequent excess risk of serious offenses and serious crashes for both men and women. In addition, negative parental influences (lenient attitudes toward young people's drinking; low monitoring, nurturance, family connectedness), were also demonstrated to increase the risk of serious offenses and serious crashes for both men and women.

Long-term follow-up of a high school alcohol misuse prevention program's effect on students' subsequent driving.

BACKGROUND: Alcohol-related injuries, particularly motor vehicle, are an important cause of adolescent mortality. School-based alcohol prevention programs have not been evaluated in terms of driving outcomes. This study examined the effects on subsequent driving of a high school-based alcohol prevention program. METHODS: The Alcohol Misuse Prevention Study included a randomized test of the effectiveness of an alcohol misuse prevention curriculum conducted among 4,635 10th-grade students. Students were assigned to intervention (n = 1,820) or control (n = 2,815) groups and were followed for an average of 7.6 years after licensure, which typically occurred during or shortly after 10th grade. Outcomes examined included alcohol-related and other serious offenses, and at-fault, single-vehicle, and alcohol-related crashes. RESULTS: Only serious offenses (which included alcohol-related) had a significant treatment effect (statistically marginal) after we adjusted for sex, age, race, alcohol use/misuse, family structure, presence of prelicense offenses, age of driver licensure, and parental attitudes toward teen drinking. The effect was found only during the first year of licensure (estimated adjusted relative risk = 0.80, confidence interval = 0.63-1.01). Two first-year serious offense interactions were found. The positive effect was strongest among the largest subgroup of students, those who were drinking less than one drink per week on average before the curriculum, compared with those who drank more than one drink per week (p = 0.009). The effect was also stronger for the small subgroup of students whose parents had not expressed disapproval of teens' drinking, compared with those whose parents had disapproved (p = 0.004). CONCLUSIONS: These findings suggest that a high school-based alcohol prevention program can positively affect subsequent driving, particularly that of students who do not use alcohol regularly. The results highlight the need to start prevention efforts early and extend them beyond the initial exposure to driving. Programs should incorporate the differing backgrounds of the students.

Changes in young adult offense and crash patterns over time.

A study of 13,809 young adult drivers in Michigan examined offenses and crashes ('incidents') for an average of 7 years after their original license date. During this period, 73% of subjects committed an offense that resulted in a conviction and 58% had a crash that was reported to the police. Forty-two percent had committed an offense classified as 'serious,' and 21% had an 'at-fault' crash. The odds of an offense being serious decreased approximately 8% per year of licensure, independent of gender or age at licensure. Similarly, the odds of a crash being at-fault decreased overall about 6% per year of licensure, but the decline was more than twice as fast for women as for men. Examining the empirical rates directly, it was found that the rate for minor offenses increased somewhat with time and then stabilized, while the rate for serious offenses declined. Also, offenses were less likely to be serious the later they occurred in the sequence of offenses for an individual. For crashes, the risk of having an at-fault crash declined more rapidly than the risk of a not-at-fault crash, although the rate of decrease began to equalize after approximately 5 years of licensure. The proportion of crashes that were at-fault did not decline over the sequence of crashes for an individual. Although crashes and offenses are positively correlated, they follow different trajectories over the early years of licensure.

Adolescent injury in the emergency department: opportunity for alcohol interventions?

STUDY OBJECTIVE: Alcohol, the most commonly used substance among adolescents, is frequently associated with injury. Little is known regarding the drinking characteristics of injured adolescents. Such data are critical for developing emergency department interventions to decrease alcohol-related injury among adolescents. We sought to describe the drinking characteristics of injured adolescents and to describe the relationship of injury severity and mechanisms with drinking characteristics. METHODS: This study was a prospective cohort study performed in a university hospital (sampled May 1, 1995, to July 15, 1995) and a large urban teaching hospital (sampled May 1, 1996, to August 1, 1996). The participants were aged 12 to 20 years, presenting within 6 hours of an injury. We performed a saliva alcohol test and self-administered questionnaire. Age, sex, E-code, injury severity score (ISS), and ED disposition were recorded. An alcohol frequency/quantity index was calculated. Descriptive statistics and 95% confidence intervals were calculated. RESULTS: Two hundred sixty-three patients with a mean age of 17 years and a mean ISS of 2.1 (SD 3.5) were recruited. One hundred fifty-two (50%) were males, and 33 (13%) were admitted. Ten (4%) patients had a positive saliva alcohol test response. On average, within the last year, these adolescents had 1.7 adverse alcohol consequences. Sixty percent drank in unsupervised settings, and 36% reported drinking 5 or more drinks in a row. CONCLUSION: Alcohol use/misuse is a substantial problem among injured adolescents regardless of severity or mechanism of injury. ED physicians should consider screening/intervention or primary prevention of alcohol problems for all injured adolescents.

Twelfth grade follow-up of the effectiveness of a middle school-based substance abuse prevention program.

A twelfth-grade follow-up afforded the opportunity to assess the long-term effects of substance abuse prevention delivered in sixth and seventh grades. A social pressures resistance skills curriculum implemented by classroom teachers had been evaluated with short-term positive results previously reported. Students completed self-administered questionnaires at sixth grade pre- and posttests, and at seventh and twelfth-grade posttests. Curriculum group students received lessons on alcohol, tobacco (cigarettes and smokeless), marijuana, and cocaine, which were later incorporated into the Michigan Model for Comprehensive School Health Education. This evaluation used data from 262 students who completed all four questionnaires and who received the complete two-year intervention or no intervention. Repeated measures analyses of variance demonstrated that significant effects evident at seventh grade for alcohol use and misuse, as well as cigarette, cocaine, and other drug use were generally not maintained through twelfth grade. Ongoing reinforcement of effective prevention is recommended.

Alcohol-related predictors of adolescent driving: gender differences in crashes and offenses.

Demographic and alcohol-related data collected from eight-grade students (age 13 years) were used in logistic regression to predict subsequent first-year driving crashes and offenses (age 17 years). For young men's crashes and offenses, good-fitting models used living situation (both parents or not), parents' attitude about teen drinking (negative or neutral), and the interaction term. Young men who lived with both parents and reported negative parental attitudes regarding teen drinking were less likely to have crashes and offenses. For young women's crashes, a good-fitting model included friends' involvement with alcohol. Young women who reported that their friends were not involved with alcohol were least likely to have crashes. No model predicting young women's offenses emerged.

Factors in adolescent drinking/driving: binge drinking, cigarette smoking, and gender.

During three consecutive years, 3,137 high school seniors from three graduating classes in one Michigan county were surveyed. The primarily White sample reported their use of alcohol and cigarettes, driving experience, and drinking/driving experience. Survey data were linked with state driver history records. Fully one-third of the high school seniors reported driving after drinking in the past six months. To identify factors associated with self-reported drinking/driving, correlation and regression analyses were conducted. Frequent binge drinking and riding with a drinking driver were consistent factors in driving after drinking frequency. Being male, smoking cigarettes, having frequent use of a motor vehicle, having a driving offense on record, and number of years licensed were important correlates, varying by year of graduation. Comprehensive interventions to moderate drinking, smoking, and driving after drinking are needed.

Effectiveness of a high school alcohol misuse prevention program.

An alcohol misuse prevention curriculum for tenth-grade students was developed, implemented, and evaluated through twelfth grade with 1041 students from four school districts. The curriculum emphasized social pressures resistance training, immediate effects of alcohol, risks of alcohol misuse, and social pressures to misuse alcohol. There were desirable program effects on alcohol misuse prevention knowledge (p < 0.001), alcohol misuse (p < 0.02), and refusal skills (p < 0.09). Gender by occasion differences were found on alcohol use, alcohol misuse, and driving after drinking, with boys' rates increasing more than those of girls. Exposure to a sixth-grade, as well as the tenth-grade, program did not result in better outcomes. Despite high levels of alcohol use among high school students, a tenth-grade curriculum can result in some desirable effects. Creative approaches are needed, however, especially for boys who tend to use and misuse alcohol at rates that increase more steeply than those of girls.

Effectiveness of a school-based substance abuse prevention program.

A grade five through eight substance abuse prevention program, later incorporated into the Michigan Model for Comprehensive School Health Education, was developed, implemented, and evaluated. Results focus on students who received seven lessons on alcohol in grade six, and eight lessons on tobacco, alcohol, marijuana, and cocaine in grade seven taught by their regular classroom teachers (after a 6-hour training in the social pressures resistance skills curriculum). Students (N = 442) received either two years of the program or none, and completed individually-coded questionnaires. Repeated measures analysis of variance resulted in significant treatment by occasion interactions on the use of alcohol, cigarettes, marijuana, cocaine, and other drugs, as well as on knowledge. At the end of grade seven, program students' rates of substance use had increased significantly less and knowledge of alcohol pressures, effects, and skills to resist had increased significantly more than those of comparison students.

Measurement of alcohol use and misuse in a cohort of students followed from grade 6 through grade 12.

In following a cohort of students from grade 6 through grade 12 for the purpose of evaluating an Alcohol Misuse Prevention Study curriculum, a substudy of the measurement of alcohol use and misuse was conducted. The 6-year follow-up of young people over time afforded a good opportunity to assess the adequacy of the initially chosen measures to 1) provide data with statistically desirable properties, and 2) be sensitive to and representative of the wide range of alcohol use and misuse patterns among adolescents as they mature. Revised measures of alcohol use and misuse were developed from the data responding to the same questionnaire items that had been used throughout the study. The revised measures demonstrated good psychometric properties and may be useful in other studies.

Longitudinal evaluation of an enhanced alcohol misuse prevention study (AMPS) curriculum for grades six-eight.

For students progressing from sixth to eighth grade, an enhanced Alcohol Misuse Prevention Study (AMPS) curriculum that emphasized social pressure resistance training, peer support, and norm-setting was developed, implemented, and evaluated. Schools were randomly assigned within communities to curriculum or control groups. Students were pretested early in sixth grade before the intervention and posttested at the end of sixth, seventh, and eighth grades. Results indicated the curriculum was effective in increasing students' knowledge of curriculum material, and among the subgroup of students who had used alcohol unsupervised by adults before the pretest, in reducing the rate of increase of alcohol misuse. The findings result from a replication of the analytic approach used with the initial AMPS cohort data.

Parental drinking and gender factors in the prediction of early adolescent alcohol use.

This study examines the relationship between children's reports of their parents' drinking patterns, and the child's alcohol misuse and heavy alcohol use in early adolescence. Subjects were 2,213 fifth and sixth grade students. Data on the child's alcohol use and misuse, and parent alcohol use, were derived from classroom-administered questionnaires. Increased reported level of drinking by mother or by father was significantly associated with increased odds of alcohol misuse and heavy alcohol use among the children; these results held for both boys and girls when examined separately. Examination for possible confounding effects of assortative mating by parental drinking suggests that reports of heavy drinking in either parent increases the risk of alcohol misuse and heavy alcohol use in children. Implications for prevention efforts are discussed.

Pathologists' participation in postmortem examinations for patients with dementia.

Pathologists (n = 571) in Michigan were surveyed to examine the problem of limited access to autopsy experienced by families of patients with dementia and to assist with the implementation of the Michigan Dementia Program. The survey determined the extent to which pathologists performed autopsies for patients with dementia and/or were willing to do so as part of a statewide Postmortem Examination Program. Responses from 394 pathologists (69%) indicated that 49% were willing to perform brain removal and 44% were interested in learning more about the statewide program. The survey results were used to recruit pathologists, to identify potential problems, and to provide baseline data against which to measure the effects of a fully implemented program.

Services for persons with dementia and their families: a survey of information and referral agencies in Michigan.

In planning a statewide Dementia Program, Michigan agencies (N = 244) providing geriatric information and referral (I&R) were surveyed to determine service availability, families' needs, and problems providing I&R for persons with dementia and their families. Home-delivered meals, nursing and social work assessments were considered more available. Medical assessment, however, was considered "very available" by only 60%. Respite and adult day care were least available and most needed. Least was known about autopsy and financial services. For several services, non-urban areas reported less availability than urban areas. With additional information and training, existing agencies could provide more available and extensive I&R for persons with dementia and their families, forming a statewide network.

Structural equation model tests of patterns of family interaction, peer alcohol use, and intrapersonal predictors of adolescent alcohol use and misuse.

A survey of 1,340 students in grades six through twelve was conducted to test, in the context of structural equation models, the predictive validity of a theoretical model of antecedents of adolescent alcohol use and misuse. Constructs including parents' alcohol use, older siblings alcohol use, parents' approval of students alcohol use, older sibling approval of students alcohol use, peer use and approval of alcohol use (PUA), parental nurturance, parental permissiveness, child's grade in school, susceptibility to peer pressure (SPP), and deviant self-image, were included. The final iterations of the models accounted for more than half of the variance in both alcohol use and alcohol misuse. In a standardized solution, the two largest direct effects on both adolescent alcohol use and misuse were from SPP and PUA. When a seven item measure of SPP, including three items specific to alcohol use was used, the SPP latent variable accounted for a somewhat greater percentage of the variance in adolescent alcohol use and misuse than did the latent variable of PUA. When the three alcohol-specific items were deleted from SPP, however, PUA accounted for more variance than SPP. Other predictors, including parental behaviors, proved to be significant when their indirect effects were evaluated. Models predicting alcohol use and alcohol misuse were similar. SPP, PUA, and other significant predictors should be included in future models predicting adolescent alcohol use and misuse, as well as in future interventions targeting these behaviors. Longitudinal studies should be used to test these findings. Evaluation of prevention should include examination of possible interactions of these predictors with each other and with subject subgroup classifications.