▪ Abstract Obesity has increased dramatically over the past two decades and currently about 50% of US adults and 25% of US children are overweight. The current epidemic of obesity is caused largely by an environment that promotes excessive food intake and discourages physical activity. This chapter reviews what is known about environmental influences on physical activity and eating behaviors. Recent trends in food supply, eating out, physical activity, and inactivity are reviewed, as are the effects of advertising, promotion, and pricing on eating and physical activity. Public health interventions, opportunities, and potential strategies to combat the obesity epidemic by promoting an environment that supports healthy eating and physical activity are discussed.

Environmental Influences on Eating and Physical Activity

We gathered information on the cost-effectiveness of life-saving interventions in the United States from publicly available economic analyses. "Life-saving interventions" were defined as any behavioral and/or technological strategy that reduces the probability of premature death among a specified target population. We defined cost-effectiveness as the net resource costs of an intervention per year of life saved. To improve the comparability of cost-effectiveness ratios arrived at with diverse methods, we established fixed definitional goals and revised published estimates, when necessary and feasible, to meet these goals. The 587 interventions identified ranged from those that save more resources than they cost, to those costing more than 10 billion dollars per year of life saved. Overall, the median intervention costs $42,000 per life-year saved. The median medical intervention cost $19,000/life-year; injury reduction $48,000/life-year; and toxin control $2,800,000/life-year. Cost/life-year ratios and bibliographic references for more than 500 life-saving interventions are provided.

Five-hundred life-saving interventions and their cost-effectiveness.

Objectives. We examined the public health consequences of unsafe and inconvenient walking and bicycling conditions in American cities to suggest improvements based on successful policies in The Netherlands and Germany. Methods. Secondary data from national travel and crash surveys were used to compute fatality trends from 1975 to 2001 and fatality and injury rates for pedestrians and cyclists in The Netherlands, Germany, and the United States in 2000. Results. American pedestrians and cyclists were much more likely to be killed or injured than were Dutch and German pedestrians and cyclists, both on a per-trip and on a per-kilometer basis. Conclusions. A wide range of measures are available to improve the safety of walking and cycling in American cities, both to reduce fatalities and injuries and to encourage walking and cycling.

/pdf/promoting-safe-walking-and-cycling-to-improve-public-health-4996wky1cd.pdf

Promoting safe walking and cycling to improve public health: Lessons from The Netherlands and Germany

The relationship between truck accidents and geometric design of road sections: Poisson versus negative binomial regressions.

Road traffic injuries are a major cause of death and disability globally, with a disproportionate number occurring in developing countries. 1 2 Road traffic injuries are currently ranked ninth globally among the leading causes of disability adjusted life years lost, and the ranking is projected to rise to third by 2020.1 In 1998, developing countries accounted for more than 85% of all deaths due to road traffic crashes globally and for 96% of all children killed.2 Moreover, about 90% of the disability adjusted life years lost worldwide due to road traffic injuries occur in developing countries.1 The problem is increasing at a fast rate in developing countries due to rapid motorisation and other factors (fig 1).3 However, public policy responses to this epidemic have been muted at national and international levels. Policy makers need to recognise this growing problem as a public health crisis and design appropriate policy responses.

#### Summary points

Injury and deaths due to road traffic crashes are a major public health problem in developing countries

More than 85% of all deaths and 90% of disability adjusted life years lost from road traffic injuries occur in developing countries

Among children aged 0-4 and 5-14 years, the number of fatalities per 100 000 population in low income countries was about six times greater than in high income countries in 1998

The highest burden of injuries and fatalities is borne disproportionately by poor people in developing countries, as pedestrians, passengers of buses and minibuses, and cyclists



Fig 1 
Trends in fatalities due to road traffic injuries for different regions of the world, 1980-95. Data from Transport Research Laboratory3



Road traffic injuries in developing countries particularly affect the productive (working) age group (15-44 years) and children. (A developing country is defined as a country that has an annual per …

https://www.bmj.com/content/bmj/324/7346/1139.full.pdf

The neglected epidemic: road traffic injuries in developing countries

Objectives. We sought to determine the association between urban sprawl and traffic fatalities. Methods. We created a sprawl index by applying principal components analysis to data for 448 US counties in the largest 101 metropolitan areas. Regression analysis was used to determine associations between the index and traffic fatalities. Results. For every 1% increase in the index (i.e., more compact, less sprawl), all-mode traffic fatality rates fell by 1.49% (P < .001) and pedestrian fatality rates fell by 1.47% to 3.56%, after adjustment for pedestrian exposure (P < .001). Conclusions. Urban sprawl was directly related to traffic fatalities and pedestrian fatalities. Subsequent studies should investigate relationships at a finer geographic scale and should strive to improve on the measure of exposure used to adjust pedestrian fatality rates.

Urban Sprawl as a Risk Factor in Motor Vehicle Occupant and Pedestrian Fatalities

Pedestrian crash trends and potential countermeasures from around the world

Pedestrians are legitimate users of the transportation system and they should, therefore, be able to use the system safely. Pedestrian needs in crossing streets should be identified, and appropriate solutions should be selected to improve pedestrian safety and access. Deciding where to mark crosswalks is only one consideration in meeting that objective. This study involved an analysis of 5 years of pedestrian crashes at 1,000 marked crosswalks and 1,000 matched unmarked comparison sites. None of the sites in this study had a traffic signal or stop sign on the approaches. Detailed data were collected on traffic volume, pedestrian exposure, number of lanes, type of median, speed limit, and other site variables. Poisson and negative binomial regressive models were used. Study results revealed that on two-lane roads the presence of a marked crosswalk alone at an uncontrolled location was associated with no difference in pedestrian crash rate, compared with an unmarked crosswalk. Further, on multilane roads wi...

Safety effects of marked versus unmarked crosswalks at uncontrolled locations: analysis of pedestrian crashes in 30 cities

Pedestrians are legitimate users of the transportation system, and they should, therefore, be able to use this system safely. Pedestrian needs in crossing streets should be identified, and appropriate solutions should be selected to improve pedestrian safety and access. Deciding where to mark crosswalks is only one consideration in meeting that objective. The purpose of this study was to determine whether marked crosswalks at uncontrolled locations are safer than unmarked crosswalks under various traffic and roadway conditions. Another objective was to provide recommendations on how to provide safer crossings for pedestrians. This study involved an analysis of 5 years of pedestrian crashes at 1,000 marked crosswalks and 1,000 unmarked comparison sites. All sites in this study had no traffic signal or stop sign on the approaches. Detailed data were collected on traffic volume, pedestrian exposure, number of lanes, median type, speed limit, and other site variables. Poisson and negative binomial regressive models were used. The study results revealed that on two-lane roads, the presence of a marked crosswalk alone at an uncontrolled location was associated with no difference in pedestrian crash rate, compared to an unmarked crosswalk. Further, on multilane roads with traffic volumes above about 12,000 vehicles per day, having a marked crosswalk alone (without other substantial improvements) was associated with a higher pedestrian crash rate (after controlling for other site factors) compared to an unmarked crosswalk. Raised medians provided significantly lower pedestrian crash rates on multilane roads, compared to roads with no raised median. Older pedestrians had crash rates that were high relative to their crossing exposure. More substantial improvements were recommended to provide for safer pedestrian crossings on certain roads, such as adding traffic signals with pedestrian signals when warranted, providing raised medians, speed-reducing measures, and others.

Safety Effects of Marked versus Unmarked Crosswalks at Uncontrolled Locations: Final Report and Recommended Guidelines

This guide is intended to provide information on how to identify safety and mobility needs for pedestrians with the roadway right-of-way. Useful for engineers, planners, safety professionals and decision-makers, the guide covers such topics as: the Walking Environment including sidewalks, curb ramps, crosswalks, roadway lighting and pedestrian over and under passes; Roadway Design including bicycle lanes, roadway narrowing, reducing the number of lanes, one-way/two-way streets, right-turn slip lanes and raised medians; Intersections with roundabouts, T-intersections and median barriers; and Traffic Calming designs.

Charles V. Zegeer

Papers

Urban Sprawl as a Risk Factor in Motor Vehicle Occupant and Pedestrian Fatalities

Pedestrian crash trends and potential countermeasures from around the world

Safety effects of marked versus unmarked crosswalks at uncontrolled locations: analysis of pedestrian crashes in 30 cities

Safety Effects of Marked versus Unmarked Crosswalks at Uncontrolled Locations: Final Report and Recommended Guidelines

Pedestrian facilities users guide. providing safety and mobility