Preliminary estimates of the effects of mandatory seat belt use laws

Analyses of motor vehicle fatality counts in New York and several comparison states for the years 1980 through 1985 indicate that New York's seat belt use law reduced fatalities by about nine percent during the first nine months of the law. This estimate is preliminary, and the estimated long-term effect of the law could change as more sophisticated analyses are applied to the data and as belt use changes (it had declined to less than 50 percent over most of the state by the end of the first year of the law). In addition, New York's law is one of the strongest in terms of enforceability, and the effect may be smaller in states with weaker laws. However, the estimated effect in New York is consistent with the experience of other countries with seat belt use laws.     

Results of a seat belt use law enforcement and publicity campaign in Elmira, New York

In New York and other states in which seat belt use laws went into effect in the mid-1980s, belt use rates surged initially, then declined. This pattern of belt use also occurred in Canadian provinces that enacted laws in the mid-1970s; special enforcement programs reversed this trend. In late 1985 a three-week enforcement and publicity program was conducted in Elmira, New York. Belt use rates in Elmira were 49 percent before the program, 77 percent right after, and 66 percent two months later. In Glens Falls, a comparison city without a program, belt use declined from 43 percent to 37 percent during this interval. In a telephone survey after the campaign, Elmira respondents were more likely to say the belt use law was being strictly enforced and were more favorable toward it, compared to Glens Falls respondents. These data indicate that enforcement/publicity programs are an important and feasible method for increasing compliance with belt use laws.     

Seat belt legislation and seat belt use: effects on differences related to sex, social class and smoking

As part of a larger study of preventive health behavior, 177 adults answered a question about how often they wore seat belts both before and after seat belt legislation was introduced in Britain. Analyses by smoking status, sex and socioeconomic status (SES) showed that all groups increased the frequency of self-reported seat belt use after the law was introduced. Regression analyses showed that before the law, SES, sex and general preventive behavior were significant predictors of seat belt use, while only SES was a significant predictor of post-legislation seat belt use. Overall the results suggested that seat belt legislation was effective in promoting seat belt use since most of the demographic differences were eliminated by the legislation.     

The effect of New York's seat belt use law on teenage drivers

This study assessed the effects of New York State's recently adopted mandatory seat belt use law on teenage drivers. Teenage drivers were observed as they entered high school parking lots before the law was adopted, after it was adopted but before it was effective, one month after the effective date, and again five months after the effective date. The results showed that 14% of the teenage drivers were wearing either shoulder or lap belts or both prior to adoption of the law. This increased to 22% after adoption of the law, 60% one month after the effective date of the law, and 63% five months after the effective date. Teenagers using seat belts were more often female, were younger, had completed driver education and had a longer trip from home to school. Both before and after the law, teenage belt use was similar to, but typically lower than, belt use in the community in which the school was located.     

Possible causes of socioeconomic and ethnic differences in seat belt use among high school students.

This study has assessed seat belt use and factors which may influence seat belt use among high school students from three types of schools. The inner city schools had high proportions of African American and Hispanic American students from low income families, whereas the middle class school and private schools had high proportions of non-Hispanic white students from middle class families with college educated parents. Students from the inner city schools reported less seat belt use than students from the middle class school or private schools. Our analyses evaluated several hypotheses concerning possible reasons why inner city youth had lower rates of seat belt use. In accord with the social influences hypothesis, inner city youth reported lower rates of parental seat belt use and less often being told by parents to use their seat belts, and our regression results indicate that less parental modeling and encouragement of seat belt use was an important cause of inner city youth's lower rates of seat belt use. Our other hypotheses received weaker support, but we did find evidence for two hypothesized differences in attitudes which influence seat belt use. Specifically, inner city youth were more likely to agree with the statement, 'there is no point in wearing seat belts since you have no control over your fate or destiny', and inner city youth attributed less importance to safety concerns as a motivation for seat belt use. These attitudes appeared to contribute to lower rates of seat belt use by inner city youth.     

Sustainability of the effects of the demerit points system on seat belt use: a region-wide before-and-after observational study in Italy

To assess the short and long term effects of the demerit points system on seat belt use, we set a region-wide cross-sectional observational study 3 months before, and 3 and 15 months after the introduction of the scheme (July 2003) in the Veneto Region, Italy. We analysed differences in seat belt use by year of observation, gender and position in the vehicle, and obtained adjusted prevalence ratio (APR) through Poisson regression. A total of 29,303 drivers, 28,778 front and 12,186 rear passengers were observed. Prevalence levels of 54% for drivers and 53% for front passengers in 2003 switched to 83 and 76%, respectively, 3 months after the new legislation, with further slight increases 15 months thereafter. Seventy-four percent rear passengers were still not compliant with the legislation in 2005. The probability of being belted was 25% lower in males than females (APR=0.75, 95% CI 0.73-0.77) at the beginning of the study period. However, the effect of the new legislation was 19% greater among males (APR=1.19, 95% CI 1.16-1.23). A substantial increase in seat belt use was reached and sustained with the demerit points system. Specific efforts should target rear passengers whose seat belt use still remains worryingly low.     

Primary enforcement seat belt laws are effective even in the face of rising belt use rates

A recent systematic literature review found that primary enforcement laws are more effective at increasing seat belt use than secondary laws in the United States. This report re-examines the studies included in the systematic review to explore whether the benefits of a primary law differ based on: (1) the baseline seat belt use rate; or (2) whether or not the primary law replaces a secondary law. States that directly enacted primary laws showed larger increases in observed seat belt use (median increase of 33 percentage points). These laws were enacted in the mid-1980s, when baseline belt use rates were below 35%. Smaller, but substantial increases in belt use were observed in states that replaced secondary with primary laws (median increase of 14 percentage points). Baseline belt use rates in these states ranged from 47 to 73%. Primary safety belt laws can further increase seat belt use even in states with relatively high baseline levels of belt use.     

The effectiveness of the Canadian mandatory seat belt use laws

The impact of four provincial mandatory seat belt use laws passed in 1976 and 1977 on seat belt use and on motor vehicle occupant casualties is examined. Subsequent to the passage of the laws, belt use typically increased from 20 to the 70% level dropping to around 50% over the next several years. Ontario exhibited a clear drop in the fatality and injury rates in the years following the introduction of the law. Quebec experienced little reduction in casualties. The changes in casualties for British Columbia and Saskatchewan were mixed with the former showing a drop only in the fatality rate subsequent to the seat belt law, while the latter experienced a reduction only in the injury rate. The provinces without seat belt use laws also enjoyed some reductions in occupant casualty rates. The changes in occupant casualties in the legislated provinces were also examined relative to the changes in non-occupant casualties and relative to the unlegislated provinces. It was concluded that three provinces experienced some reductions as a result of legislation but not as much as anticipated. It is speculated that the impact of the seat belt use laws fell short of expectations because it was mainly the safe drivers who buckled up in response to the laws.     

Seat belt use and accident involvement: A comparison of driving behavior before and after a seat belt law

In an earlier study, researchers at the University of North Carolina Highway Safety Research Center found drivers classified as seat belt nonusers on the basis of direct observation and self-reported belt use to be overrepresented in prior accidents and violations. This study represents a follow-up and extension of the earlier study where accident and violation rates over a 2.5-year interval following the classification by seat belt use status are compared. Seat belt nonusers were again found to be overrepresented in both accidents and violations. In other analyses of these data, changes in seat belt use status were found not to be associated with changes in accident or violation rates, and seat belt use rates reported by police in accidents following the mandatory seat belt law greatly exceeded both the observed and self-reported use rates. This was especially pronounced for drivers who responded that they rarely or never used seat belts.     

Getting Americans to buckle up: the efficacy of state seat belt laws

Annual state observed safety belt use rates over the period 1991–2001 are examined using time-series cross-section regression analysis. It was found that seat belt laws are associated with higher use rates and that the enforcement provision matters. Primary states experience belt use rates that on average are 9.1 percentage points higher than their secondary counterparts. In addition, the level of the fine imposed by statute has an effect on safety belt use apart from that attributable to the enforcement provision. The current median fine of $25 is associated with an additional 3.8 percentage points increase in belt use. To further increase safety belt use, it is recommended that states adopt primary enforcement and impose fines of at least $50 for violating a seat belt law.     

Geographic and sociodemographic variation in self-reported seat belt use in the United States

Background

With new data available, we sought to update existing literature on the prevalence of self-reported seat belt use by state, region, and rural/urban status and to estimate the strength of the association between seat belt use and rural/urban status adjusted for type of seat belt law and several other factors.

Methods

We examined data on self-reported use of seat belts from 50 states, the District of Columbia, and three territories using the 2008 Behavioral Risk Factor Surveillance System, a state-based random-digit-dialed telephone survey (n = 406,552). Reported seat belt use was assessed by state, U.S. Census regions, and U.S. Department of Agriculture (USDA) rural/urban continuum codes.

Results

Overall, 85% of adults in the United States reported they always used seat belts. Regionally, the West had the highest prevalence of persons who reported that they always wear seat belts (89.6%) and the Midwest had the lowest (80.4%). States with primary seat belt laws had the highest prevalence of reported seat belt use, compared with states with secondary or no laws. After adjusting for various sociodemographic characteristics, body mass index, and type of seat belt law, persons in the most densely populated metropolitan areas were significantly more likely to report always wearing seat belts than those in most sparsely populated rural areas (adjusted odds ratio = 2.9).

Conclusion

Our findings reinforce the evidence that primary enforcement seat belt laws are effective for increasing seat belt use, and suggest that upgrading to primary enforcement laws will be an important strategy for reducing crash-related fatalities in rural areas.     

An investigation of factors reducing seat belt use amongst Spanish drivers and passengers on urban roads

Seat belt use on Spain's highways is more than 80%, while on the urban roads this figure is around 50%. As there was little information available to explain the difference in seat belt use rates, the main aim of this study was to investigate why there is a lower rate of seat belt use on urban roads. A number of perceptions, beliefs and expectancies about seat belt use were examined to identify variables that discriminated between seat belt users and non-users on urban roads. The subjects were 398 undergraduate students (aged 17-47) studying at the University of Girona, Spain. On the urban roads reported discomfort from using the seat belt was higher, while perceptions of risk (for non-users), safety perceptions (for those using a seat belt), beliefs about the seriousness of a crash or the effectiveness of the seat belt were all lower than on the highway. Perceptions of safety, discomfort, and social influence predicted seat belt use on urban roads. Concern about being fined for not using a seat belt did not predict seat belt use. The results of this research suggest that in order to increase seat belt use on urban roads, the issue of discomfort must be addressed. In addition, prevention campaigns should include information about the effectiveness of the seat belt in preventing/reducing injuries or deaths on urban roads. The results also highlight the importance of social influence for determining seat belt use/non-use and the potential role social influence could play in increasing seat belt usage.     

Extra enforcement and the use of seat belts by drivers in Illinois

The use of seat belts by drivers was measured in three target and three control cities in Illinois before, during, and after the application of heightened police enforcement of the seat belt law in the target cities. The extra enforcement produced increases in the use of seat belts by drivers during the four months of the heightened enforcement. Observations of seat belt use continued for four months after the end of the enforcement, and a substantial residual effect remained in two of the three target cities. In one target city the use of seat belts had dropped close to the level at the start of the project by the end of the second month after the end of enforcement. Taking account of the percentage of drivers who became aware of the increased enforcement suggested that a sustained program of enforcement may result in 60%–70% of drivers using seat belts.     

Self-reported and observed seat belt use – A case study: Bosnia and Herzegovina

The issue of seat belt use in middle- and low-income countries is strongly evident and has as a result higher rates of fatalities and seriously injured on the roads. The first systematic field research of the seat belt use while driving was carried out in Bosnia and Herzegovina, in 2011–2012. Research methodology consisted of two mutually conditioned parts (observation and self-reported behavior). Specific features of the methodology used are in the relationship between the observed and interviewed drivers which enabled the analysis of their observed and self-reported behavior while driving. The logistic regression method was used in this work to make the analysis of the influence of personal human characteristics (gender, age, education, exposure) and vehicles’ characteristics (age) on the observed and self-reported driving behavior, from the point of view of seat belt use while driving. The influence of the listed factors on driving behavior, depending on road type (urban or rural), was given special attention in the analysis. The paper shows that certain factors do not have the same impact on driving behavior, in various conditions. Based on results from this study, it will be possible to define certain critical groups of road users and the way in which they must be addressed in order to increase the seat belt wearing rate.     

How would increasing seat belt use affect the number of killed or seriously injured light vehicle occupants?

The expected effects of increasing seat belt use on the number of killed or seriously injured (KSI) light vehicle occupants have been estimated for three scenarios of increased seat belt use in Norway, taking into account current seat belt use, the effects of seat belts and differences in crash risk between belted and unbelted drivers. The effects of seat belts on fatality and injury risk were investigated in a meta-analysis that is based on 24 studies from 2000 or later. The results indicate that seat belts reduce both fatal and non-fatal injuries by 60% among front seat occupants and by 44% among rear seat occupants. Both results are statistically significant. Seat belt use among rear seat occupants was additionally found to about halve fatality risk among belted front seat occupants in a meta-analysis that is based on six studies. Based on an analysis of seat belt wearing rates among crash involved and non-crash involved drivers in Norway it is estimated that unbelted drivers have 8.3 times the fatal crash risk and 5.2 times the serious injury crash risk of belted drivers. The large differences in crash risk are likely to be due to other risk factors that are common among unbelted drivers such as drunk driving and speeding. Without taking into account differences in crash risk between belted and unbelted drivers, the estimated effects of increasing seat belt use are likely to be biased. When differences in crash risk are taken into account, it is estimated that the annual numbers of KSI front seat occupants in light vehicles in Norway could be reduced by 11.3% if all vehicles had seat belt reminders (assumed seat belt wearing rate 98.9%), by 17.5% if all light vehicles had seat belt interlocks (assumed seat belt wearing rate 99.7%) and by 19.9% if all front seat occupants of light vehicles were belted. Currently 96.6% of all (non-crash involved) front seat occupants are belted. The effect on KSI per percentage increase of seat belt use increases with increasing initial levels of seat belt use. Had all rear seat occupants been belted, the number of KSI front seat occupants could additionally be reduced by about 0.6%. The reduction of the number of KSI rear seat occupants would be about the same in terms of numbers of prevented KSI.     

Improving seat belt use among teen drivers: Findings from a service-learning approach

Background

Low seat belt use and higher crash rates contribute to persistence of motor vehicle crashes as the leading cause of teenage death. Service-learning has been identified as an important component of public health interventions to improve health behavior.

Methodology

A service-learning intervention was conducted in eleven selected high schools across the United States in the 2011–2012 school year. Direct morning and afternoon observations of seat belt use were used to obtain baseline observations during the fall semester and post-intervention observations in the spring. The Mann–Whitney U test for 2 independent samples was used to evaluate if the intervention was associated with a statistically significant change in seat belt use. We identified factors associated with seat belt use post-intervention using multivariable logistic regression.

Results

Overall seat belt use rate increased by 12.8%, from 70.4% at baseline to 83.2% post-intervention (p < 0.0001). A statistically significant increase in seat belt use was noted among white, black, and Hispanic teen drivers. However, black and Hispanic drivers were still less likely to use seat belts while driving compared to white drivers. Female drivers and drivers who had passengers in their vehicle had increased odds of seat belt use.

Conclusion

A high school service-learning intervention was associated with improved seat belt use regardless of race, ethnicity, or gender, but did not eliminate disparities adversely affecting minority youth. Continuous incorporation of service-learning in high school curricula could benefit quality improvement evaluations aimed at disparities elimination and might improve the safety behavior of emerging youth cohorts.     

Seat belt utilization in Saudi Arabia and its impact on road accident injuries

Most industrialized countries and many developing countries have passed laws that require the use of seat belts in motor vehicles. It is widely believed that seat belt use is an effective way to reduce road accident fatalities and injuries. Saudi Arabia joined these countries when it enacted a similar law on 5 December 2000 making seat belt use compulsory for all drivers and front-seat passengers. This study measures seat belt use rate and its impact on the number of road accident injuries during the first few months that followed the enactment of the law. It also investigates drivers' behaviour and personal characteristics and their relationship with using seat belts by using a questionnaire specially prepared for this purpose. Results show that seat belt use rate in two Riyadh suburbs were 33% and 87%, respectively, for drivers and 4% and 41%, respectively, for front-seat passengers (FSP's). Such belt use rates are considered low yet encouraging when compared with use rates before enacting the law. Results also show that there was a significant drop in certain types of injuries due to traffic accidents after the enactment of the seat belt law. Questionnaire results show that certain personal characteristics were correlated with seat belt use rate. Finally, implications of these findings in terms of future plans for improving traffic safety are discussed.     

Correlates of reported attitude towards and use of seat belts

This paper examines the relationships among self-reported seat-belt use, attitudes towards compulsory seat-belt use, and individual differences dimensions in samples of 91 females and 89 males ranging in age from 18 to 24 yr. The results show (a) support for the compulsory use of seat belts (78% for females, 66% for males); (b) significant relationships between reported seat belt use and four fear of death and dying subscales; and, (c) no relationships between the seat-belt variables and Eysenckian personality variables. One caveat is that the generalizability of results from this student sample to other driver populations may be limited.     

Predicting seat belt use in fatal motor vehicle crashes from observation surveys of belt use

There is a large difference between the rates of observed seat belt use by the general public and belt use by motor vehicle occupants who are fatally injured in crashes. Seat belt use rates of fatally injured occupants, as reported in the Fatality Analysis Reporting System (FARS), are much lower than the use rates found in observation surveys conducted by the states. A series of mathematical models describing the empirical relationship between FARS and observed rates were explored. The initial model was a 'straw man' and used two simplifying assumptions: (a) belt users and nonusers are equally likely to be involved in 'potentially fatal collisions', and (b) belts are 45% effective in preventing deaths. The model was examined by comparing each state's FARS use rate with the predicted rate. The model did not fit the state data points even when possible biases in the data were controlled. We next examined the assumptions in the model. Changing the seat belt effectiveness parameter provided a reasonable fit, but required an assumption that seat belts are 67% effective in preventing fatalities. The inclusion of a risk coefficient for non-belted occupants also provided a reasonable fit between the model and data. A variable risk model produced the best fit with the data. The major finding was that a model consistent with the data can be obtained by incorporating the assumption that nonusers of seat belts have a higher risk of involvement in potentially fatal collisions than do seat belt users. It was concluded that unbelted occupants are over-represented in fatal collisions for two reasons: (a) because of a greater chance of involvement in potentially fatal collisions in the first place, and (b) because they are not afforded the protection of seat belts when a collision does occur.     

Belt use by high-risk drivers before and after New York's seat belt use law

Belt use among drivers traveling on limited access highways was observed before and after New York's mandatory seat belt use law. The results showed that high-speed drivers had lower belt use rates before the law and increased their belt use less in response to the law. Belt use rates before the law were 25%, 29%, and 28% for the high-, medium-, and low-speed groups as compared with 51%, 64%, and 57%, respectively, after the law. High-speed drivers also had inferior previous driving records, confirming their higher risk of motor vehicle crash involvement.