Graduated Driver Licensing Research, 2007-Present: A Review and Commentary

The evolution of graduated licensing systems in the past 25 years has resulted in dramatic growth in research on this topic. The most recent summary reports have covered the period up to 2007. In the present article more recent and ongoing research is categorized, summarized, and discussed.     

Crash involvement during the different phases of the New Zealand Graduated Driver Licensing System (GDLS)

Introduction

The New Zealand Graduated Driver Licensing System (GDLS) is designed to allow novice drivers to gain driving experience under conditions of reduced risk.

Method

To examine the effectiveness of the GDLS, an analysis of how the crash involvement of novice drivers changes as drivers move through the GDLS was undertaken. Crash profiles were created by data matching the New Zealand license and crash databases, covering a time period from 1999-2006.

Results

The crash profiles show that the initial learner period of the GDLS is relatively safe and the time at which novice drivers have the highest rate of crash involvement is during the first few months of solo driving. Analysis using logistic regression also showed an effect of age and gender, with higher crash involvement associated with younger drivers and males. In addition, individuals who gained a full license within 12-18 months of holding a restricted license, due to completion of a time-discount associated educational program, had a higher level of involvement in crashes than individuals who gained a full license after 18 months.

Conclusions

The crash profiles provide an insight into the crash risk associated with different phases of the New Zealand GDLS.

Impact on Industry

Increasing the age at which drivers first begin to solo drive and the removal of the time-discount associated with completion of an educational program should be considered.     

Bicycle helmet use among children in the United States: The effects of legislation, personal and household factors

Introduction

Children ages 5-14 years have the highest rate of bicycle-related injuries in the country. Bicycle helmets can prevent head and brain injuries, which represent the most serious type of bicycle-related injury.

Objectives

This paper compares children's bicycle helmet use to that estimated from an earlier study, and explores regional differences in helmet use by existing helmet legislation.

Methods

This study was a cross-sectional, list-assisted random-digit-dial telephone survey. Interviews were completed by 9,684 respondents during 2001-2003. The subset with at least one child in the household age 5-14 years (2,409 respondents) answered questions about bicycle helmet use for a randomly selected child in their household.

Results

Almost half (48%) of the children always wore their helmet, 23% sometimes wore their helmet, and 29% never wore their helmet. Helmet wearing was significantly associated with race, ethnicity, and child age but was not associated with the sex of the child. Other significant predictors of use included household income, household education, census region, and bicycle helmet law status. Statewide laws were more effective than laws covering smaller areas. The proportion of children who always wore a helmet increased from 25% in 1994 to 48% in 2001-2002. Significant increases in helmet use from 20% to 26% were seen among both sexes, younger (5-9 years) and older (10-14 years) children, and in all four regions of the country.

Conclusions

While there has been substantial progress in the number of children who always wear their helmets, more than half do not. Further progress will require using a combination of methods that have been shown to successfully promote consistent helmet use. Impact on industry: minimal.     

Examining traffic crash injury severity at unsignalized intersections

Introduction

This study presents multiple approaches to the analysis of crash injury severity at three- and four-legged unsignalized intersections in the state of Florida from 2003 until 2006. An extensive data collection process was conducted for this study.

Method

The dataset used in the analysis included 2,043 unsignalized intersections in six counties in the state of Florida. For the scope of this study, there were three approaches explored. The first approach dealt with the five injury levels, and an ordered probit model was fitted. The second approach was an aggregated one, and dealt with only the severe versus non-severe crash levels, and a binary probit model was used. The third approach dealt with fitting a nested logit model. Results from the three fitted approaches were shown and discussed, and a comparison between the three approaches was shown.

Results

Several important factors affecting crash severity at unsignalized intersections were identified. These include the traffic volume on the major approach, and the number of through lanes on the minor approach (surrogate measure for traffic volume), and among the geometric factors, the upstream and downstream distance to the nearest signalized intersection, left and right shoulder width, number of left turn movements on the minor approach, and number of right and left turn lanes on the major approach. As for driver factors, young and very young at-fault drivers were associated with the least fatal probability compared to other age groups.

Impact on industry

The analysis identified some countermeasures to reduce injury severity at unsignalized intersections. The spatial covariates showed the importance of including safety awareness campaigns for speeding enforcement. Also, having a 90-degree intersection design is the most appropriate safety design for reducing severity. Moreover, the assurance of marking stop lines at unsignalized intersections is very essential.     

Behavior and lifestyle characteristics of male Kuwaiti drivers

Introduction: The high traffic accident risk among young drivers is a well-known and well-documented fact in most countries. Lifestyle has proven to affect driving behavior as well as accident risk. This study covers the lifestyle component of the problems related to young male Kuwaiti drivers’ accident risk. Methods: The purpose of the study is to measure the relationship between lifestyle and accident risk. Lifestyle is measured through a questionnaire, where 302 male Kuwaiti drivers (mean age = 28 years; range 25-35 years) answer 39 questions related to behavioral and social factors, road conditions, police enforcement, and life satisfaction. They also report their involvement in accidents and traffic violations. Results: The questionnaire's validity and reliability (Cronbach's alpha = 0.7) were achieved. Principal component analysis reduced the 39 items on the questionnaire to 5 factors. Inadequate police enforcement is strongly correlated (r = 0.862) to accident risk and traffic violations and is thus considered the best predictor of traffic accidents in Kuwait. Impact on Industry: As driving-related incidents (on-the-job and off-the-job) are a significant source of fatalities and lost-work-days, the study points to the importance of considering cultural factors in the design of comprehensive safety programs for industry.     

The development and validation of a psychological contract of safety scale

Introduction

This paper builds on previous research by the author and describes the development and validation of a new measure of the psychological contract of safety. The psychological contract of safety is defined as the beliefs of individuals about reciprocal safety obligations inferred from implicit and explicit promises.

Method

A psychological contract is established when an individual believes that perceived employer and employee safety obligations are contingent on each other. A pilot test of the measure is first undertaken with participants from three different occupations: nurses, construction workers, and meat processing workers (N = 99). Item analysis is used to refine the measure and provide initial validation of the scale. A larger validation study is then conducted with a participant sample of health care workers (N = 424) to further refine the measure and to determine the psychometric properties of the scale.

Results

Item and correlational analyses produced the final employer and employee obligations scales, consisting of 21 and 17 items, respectively. Factor analyses identified two underlying dimensions in each scale comparable to that previously established in the organizational literature. These transactional and relational-type obligations provided construct validity of the scale. Internal consistency ratings using Cronbach's alpha found the components of the psychological contract of safety measure to be reliable.

Impact on Industry

The refined and validated psychological contract of safety measure will allow investigation of the positive and negative outcomes associated with fulfilment and breach of the psychological contract of safety in future research.     

Follow-up of pregnancies complicated by placental mosaicism diagnosed by chorionic villus sampling

Thirty-nine (2.3 per cent) of 1724 chromosome studies from diagnostic chorionic villus samplings (CVS) done between 1983 and 1990 showed either level III (true) mosaicism (1.2 per cent) or level II (pseudo-) mosaicism (1.1 per cent) for chromosomal aneuploidy. Follow-up information on these 39 pregnancies was collected from questionnaires to families, paediatricians, and obstetricians. For all cases in which the pregnancy was continued and further testing was accomplished, the mosaicism was felt to be confined to the placenta. As compared with a control group of pregnancies evaluated by CVS with normal karyotypes, there was no increased incidence of pregnancy loss, congenital malformations, or developmental delay in the infants. Although intrauterine growth retardation occurred in several of the level III mosaic cases, adequate catch-up growth has been demonstrated.     

Evaluation of spatial and temporal variations in marine sediments quality using multivariate statistical techniques

Spatial and temporal variations of sediment quality in Matanzas Bay (Cuba) were studied by determining a total of 12 variables (Zn, Cu, Pb, As, Ni, Co, Al, Fe, Mn, V, CO₃ ^2?, and total hydrocarbons (THC). Surface sediments were collected, annually, at eight stations during 2005–2008. Multivariate statistical techniques, such as principal component (PCA), cluster (CA), and lineal discriminant (LDA) analyses were applied for identification of the most significant variables influencing the environmental quality of sediments. Heavy metals (Zn, Cu, Pb, V, and As) and THC were the most significant species contributing to sediment quality variations during the sampling period. Concentrations of V and As were determined in sediments of this ecosystem for the first time. The variation of sediment environmental quality with the sampling period and the differentiation of samples in three groups along the bay were obtained. The usefulness of the multivariate statistical techniques employed for the environmental interpretation of a limited dataset was confirmed.     

Bioavailability of diuron,imazapic and isoxaflutole in soils of contrasting textures

This research was aimed at understanding the dynamics of the herbicides diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], imazapic [2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-5-methylnicotinic acid] and isoxaflutole [5-cyclopropyl-4-(2-methanesulfonyl-4-trifluoromethyl benzoyl)isoxazole] in two soils of different physico-chemical properties. To accomplish such intent, several greenhouse experiments were run. The bioavailability of diuron (0; 1.6 and 3.2 kg ha^{? 1}), imazapic (0; 98 and 122.5 g ha^{? 1}) and isoxaflutole (0; 35 and 70 g ha^{? 1}) was measured in samples from a sandy loam soil and a clay soil, by sowing a bioindicator (Brachiaria decumbens), at 0, 25, 50, 75 and 100 days after herbicides application (DAA). Diuron was very stable in clay soil, providing control equal to or higher than 92% of bioindicator, up to 100 DAA, as assumed by biomass accumulation. No differential effect was observed in sandy loam soil, even when 2x labeled rate were applied. Imazapic provided a short bioavailability in relation to B. decumbens, independent of rates applied. The persistence of isoxaflutole was longer in clay soil (28 to 30 days).     

Television news' coverage of motor-vehicle crashes

Problem

Traffic crashes are a major cause of injury and death. Although it has been argued that a skewed estimation of personal risks may be partly attributable to news representations of mortality causes, the manners in which traffic crashes are covered in the news have not received much attention in the literature.

Method

The current study used content analysis to examine the framing of traffic crashes in television news.

Results

The data indicated that Flemish television news does not report traffic crashes from a public health perspective and consequently it misses opportunities to inform the public on the causes and consequences of risk-taking in traffic.

Impact on industry

It is important that professionals are aware of these findings and stress contextual factors surrounding traffic crashes in their communication with journalists. This may lead to more accurate reports and a more accurate risk perception of viewers.