Dorothy Jean Begg

Personality differences predict health-risk behaviors in young adulthood: evidence from a longitudinal study.

In a longitudinal study of a birth cohort, the authors identified youth involved in each of 4 different health-risk behaviors at age 21: alcohol dependence, violent crime, unsafe sex, and dangerous driving habits. At age 18, the Multidimensional Personality Questionnaire (MPQ) was used to assess 10 distinct personality traits. At age 3, observational measures were used to classify children into distinct temperament groups. Results showed that a similar constellation of adolescent personality traits, with developmental origins in childhood, is linked to different health-risk behaviors at 21. Associations between the same personality traits and different health-risk behaviors were not an artifact of the same people engaging in different health-risk behaviors; rather, these associations implicated the same personality type in different but related behaviors. In planning campaigns, health professionals may need to design programs that appeal to the unique psychological makeup of persons most at risk for health-risk behaviors.

Graduated Driver Licensing: The New Zealand Experience.

In New Zealand, on 1 August 1987, a three-stage graduated driver licensing (GDL) system that applied to all new drivers aged 15-24 years was introduced. The essential elements of GDL were a 6-month learner license (supervised driving) and an 18-month restricted license stage (with restrictions on night driving and carrying passengers). A blood alcohol limit of 0.03 mg% applied at both stages. EVALUATION STUDIES: Early studies indicated that young people were reasonably accepting of the restrictions, with the passenger restriction being the least acceptable. Problems of compliance with the restricted license driving restrictions were reported. Evaluations of the impact of the graduated driver licensing (GDL) on serious traffic-related injury showed that up until 1991-1992, an 8% reduction could be attributed to GDL. At this time, it was considered that reduced exposure was the main reason for this reduction. However, the number of fatalities and hospital admissions among young people continued to decline, as did the population rate and the rate per number of licensed drivers among the young driver age group. A further evaluation study showed that drivers with a restricted license had a smaller proportion of crashes at night, and with passengers, compared with drivers licensed before GDL. IMPACT OF GDL: These results suggested that GDL restrictions had contributed to the reduction in crashes among young people and that it was not simply a case of reduced exposure to risk. An update of the most recent crash statistics indicated that, compared with older age groups, the fatal and serious injury crash rate among young people has remained substantially below the pre-GDL level. This suggests that the impact of GDL has not diminished over time.

IDENTIFYING FACTORS THAT PREDICT PERSISTENT DRIVING AFTER DRINKING, UNSAFE DRIVING AFTER DRINKING, AND DRIVING AFTER USING CANNABIS AMONG YOUNG ADULTS

UNLABELLED The main aim of this study was to identify adolescent/young adulthood factors that predicted persistent driving after drinking, persistent unsafe driving after drinking, and persistent cannabis use and driving among young adults. It was a longitudinal study of a birth cohort (n=933, 474 males and 459 females) and was based on data collected at ages 15, 18, 21 and 26 years. At each of these ages members of the cohort attended the research unit for a personal interview by a trained interviewer, using a standardised questionnaire. For this study, the data for the outcome measures (persistent driving after drinking, persistent unsafe driving after drinking, and persistent driving after using cannabis) were obtained at ages 21 and 26 years. The main explanatory measures were collected at ages 15, 18, 21 years and included demographic factors (academic qualifications, employment, parenting); personality measures; mental health measures (substance use, cannabis dependence, alcohol dependence, depression); anti-social behaviour (juvenile arrest, aggressive behaviour, court convictions); early driving behaviour and experiences (car and motorcycle licences, traffic crashes). The analyses were conducted by gender. The results showed that females who persisted in driving after drinking (13%, n=61) were more likely than the others to have a motorcycle licence at 18. The males who persisted in driving after drinking (28%, n=135) were more likely than the other males to have some school academic qualifications and to be employed at age 26. Compared to the other males, those who persisted in unsafe driving after drinking (4%, n=17) were more likely to be aggressive at 18 and alcohol dependent at 21. Only six (1%) females persisted in unsafe driving after drinking so regression analyses were not conducted for this group. For persistent driving after using cannabis, the univariate analyses showed that females who persisted with this behaviour tended to have high substance use at 18, cannabis dependence at 21, police contact as a juvenile, and to be a parent at 21. For this group, because of the small numbers (3%, n=13) multivariate analyses were not appropriate. For the males who persisted in driving after using cannabis (14%, n=68) a wide range of variables were significant at the univariate stage. The multivariate analysis showed that the most important factors were dependence on cannabis at 21, at least one traffic conviction before 21, a non traffic conviction before 18, and low constraint at 18. CONCLUSION These results show different characteristics were associated with persistence in each of these outcome behaviours. This indicates that different approaches would be required if intervention programmes were to be developed to target these behaviours.

Minimum Purchasing Age for Alcohol and Traffic Crash Injuries Among 15- to 19-Year-Olds in New Zealand

OBJECTIVES In 1999, New Zealand lowered the minimum purchasing age for alcohol from 20 to 18 years. We tested the hypothesis that this increased traffic crash injuries among 15- to 19-year-olds. METHODS Poisson regression was used to compute incidence rate ratios for the after to before incidence of alcohol-involved crashes and hospitalized injuries among 18- to 19-year-olds and 15- to 17-year-olds (20- to 24-year-olds were the reference). RESULTS Among young men, the ratio of the alcohol-involved crash rate after the law change to the period before was 12% larger (95% confidence interval [CI]=1.00, 1.25) for 18- to 19-year-olds and 14% larger (95% CI=1.01, 1.30) for 15- to 17-year-olds, relative to 20- to 24-year-olds. Among young women, the equivalent ratios were 51% larger (95% CI=1.17, 1.94) for 18- to 19-year-olds and 24% larger (95% CI=0.96, 1.59) for 15- to 17-year-olds. A similar pattern was observed for hospitalized injuries. CONCLUSIONS Significantly more alcohol-involved crashes occurred among 15-to 19-year-olds than would have occurred had the purchase age not been reduced to 18 years. The effect size for 18- to 19-year-olds is remarkable given the legal exceptions to the pre-1999 law and its poor enforcement.

Sport and delinquency: an examination of the deterrence hypothesis in a longitudinal study.

OBJECTIVE: To determine whether involvement in sporting activity in mid-adolescence would deter delinquent behaviour in late adolescence. METHODS: Members of a longitudinal cohort study were interviewed at ages 15 and 18 years and, among other topics, were asked questions relating to involvement in physical activity and delinquent behaviour. Logistic regression models were used to examine the relation between sports involvement and delinquency at age 15 years and delinquency at age 18. RESULTS: After controlling for delinquent behaviour and psychosocial factors at age 15, females with moderate or high levels of sporting activity, and males with high levels of sporting activity, were significantly more likely to be delinquent at age 18 years than those with low levels of sporting activity. No significant association was found between sporting activity and aggressive behaviour, team sport participation and delinquency, and team sport participation and aggressive behaviour. CONCLUSIONS: This study did not support the deterrence hypothesis and showed that high involvement in sporting activity, but not team sport, was associated with a subsequent increase in delinquent behaviour.

Validity of self reported crashes and injuries in a longitudinal study of young adults

Objectives—The aim of this study was to determine the validity of self report as a source of information on crashes and injuries. Setting—This study was part of the Dunedin Multidisciplinary Health and Development Study (DMHDS), which is a longitudinal study of the health, development, and behaviour of a cohort of young New Zealanders. Method—At the age 21 assessment DMHDS study members were asked to report serious injury and motor vehicle traffic crashes experienced over the previous three years. The self reported injuries were compared with the New Zealand Health Information Service (NZHIS) public hospital discharge file to determine the completeness of the self reported data. The traffic crashes were compared with the police traffic crash reports to determine the accuracy of self reported crash details. Results—Twenty five (86%) of the 29 unintentional injuries, six (67%) of the nine assaults, and one (14%) of the six self inflicted injuries on the NZHIS file were self reported. The level of agreement between the self reported crash details and those recorded on the traffic crash report was high. Conclusions—The results show that self reports can be a useful and valid source of injury and crash data.

Seat-Belt Use and Related Behaviors Among Young Adults

Seat-belt use among young adults was examined to identify factors associated with nonuse. This research was part of the Dunedin Multidisciplinary Health and Development Study, which is a study of the health, development, and behavior of a birth cohort of young New Zealanders (n = 1037). At age 21 years, 948 (93%) members of this cohort were administered a face-to-face interview where they were asked about seat-belt use (self and friends), reasons for nonuse, and also their involvement in risky driving practices, motor-vehicle traffic crashes, and some thrill-seeking activities. Results showed relatively high front seat-belt use (85-96%) but low rear use (29-47%). Some differences in use were a function of gender and seating location. Generally, users had higher academic qualifications and lower risky driving behavior (males only), but did not differ significantly as far as crash experiences and thrill-seeking activity was concerned. The main reasons for not using a seat belt were forgetfulness/laziness, a perceived low risk of injury, and discomfort. This study provided information about the background and behavior of young adults who do not use seat belts, which could be helpful when designing strategies to promote seat-belt use in this age group.

A longitudinal study of lifestyle factors as predictors of injuries and crashes among young adults

This study was part of the Dunedin Multidisciplinary Health and Development Study. This is a longitudinal study of the health, development and behaviour of a cohort of 1037 young people born in Dunedin, New Zealand between 1 April 1972 and 31 March 1973. Explanatory measures covering background, behavioural and personality factors were obtained at ages 15 and 18 and were used as potential predictors of outcomes reported at age 21. Four outcomes were considered: any crash, injury crash, non-injury crash, and serious injury (not motor vehicle related). Overall, very few lifestyle factors were important predictors of any of these outcomes. Factors that were shown to predict injury crashes differed from those that predicted non-injury crashes. Also, those that predicted a traffic crash differed from those that predicted a serious non-traffic injury. These results suggest that focusing injury prevention efforts on changing the lifestyles of young adults is unlikely to reduce overall crash risk, and would have little impact on the risk of serious injury.

THE NEW ZEALAND GRADUATED DRIVER LICENSING SYSTEM: TEENAGERS' ATTITUDES TOWARDS AND EXPERIENCES WITH THIS CAR DRIVER LICENSING SYSTEM

OBJECTIVES: This study examined the attitudes of teenagers towards the New Zealand graduated driver licensing system (GDLS), and the extent to which it affected them. METHOD: Teenagers, who are members of a longitudinal study of a birth cohort, were interviewed at 15 years of age when the GDLS was first introduced and before they had begun licensure, and again at 18 years of age after they had experience with this licensing system. RESULTS: At both ages the majority (over 70%) agreed with the driving restrictions imposed by this system. After experience with the restrictions, however, significantly more reported being affected a lot by them, than had expected to be at age 15. This was especially true of the restrictions on the carrying of passengers and the night time curfew (10 pm - 5 am). However, few reported that they were affected by the alcohol restriction. Sixty eight per cent of those with a graduated licence reported breaking at least one of the conditions, most frequently carrying passengers. Very few were penalised by the police for this. CONCLUSIONS: Generally these young drivers were positively disposed towards the driving restrictions, but noncompliance was common. A full evaluation of all aspects of this licensing system is recommended.

Personality factors as predictors of persistent risky driving behavior and crash involvement among young adults

Objectives: The aim of this study was to examine the relationship between personality factors assessed during adolescence and persistent risky driving behavior and traffic crash involvement among young adults. Design: Data for this investigation were drawn from the Dunedin Multidisciplinary Health and Development Study, a longitudinal study of a cohort born in Dunedin, New Zealand. Subjects: The study population was 1037 young people born between 1 April 1972 and 31 March 1973. Main outcome measures: The main outcome measures were persistent risky driving behaviors and crash involvement, collected in a face-to-face road-safety interview at ages 21 and 26. Results: The only outcomes for which there were sufficient numbers of females were a driver involved in any crash and a driver involved in an injury crash. Univariate logistic regression revealed that there were no significant predictors for either of these outcomes. For the males, at the univariate level, aggression, traditionalism, and alienation were the personality scales most frequently associated with risky driving behavior and crash risk. After adjusting for driving exposure, only high levels of aggression predicted being a driver involved in a crash, and alienation predicted being a driver involved in an injury crash. Conclusion: These results suggest that road-safety interventions seeking to deter young adult males from persistent risky driving behavior need to be directed at those who do not endorse traditional views, are aggressive, and feel alienated from the rest of society.