Randomised controlled trial of a financial incentive for increasing the number of daily walking steps: study protocol

INTRODUCTION

Physical activity is one of the major modifiable factors for promotion of public health. Although it has been reported that financial incentives would be effective for promoting health behaviours such as smoking cessation or attendance for cancer screening, few randomised controlled trials (RCTs) have examined the effect of financial incentives for increasing the number of daily steps among individuals in a community setting. The aim of this study is to investigate the effects of financial incentives for increasing the number of daily steps among community-dwelling adults in Japan.

METHODS AND ANALYSIS

This study will be a two-arm, parallel-group RCT. We will recruit community-dwelling adults who are physically inactive in a suburban area (Nakayama) of Sendai city, Japan, using leaflets and posters. Participants that meet the inclusion criteria will be randomly allocated to an intervention group or a waitlist control group. The intervention group will be offered a financial incentive (a chance to get shopping points) if participants increase their daily steps from their baseline. The primary outcome will be the average increase in the number of daily steps (at 4-6 weeks and 7-9 weeks) relative to the average number of daily steps at the baseline (1-3 weeks). For the sample size calculation, we assumed that the difference of primary outcome would be 1302 steps.

ETHICS AND DISSEMINATION

This study has been ethically approved by the research ethics committee of Tohoku University Graduate School of Medicine, Japan (No. 2018-1-171). The results will be submitted and published in a peer-reviewed scientific journal.

TRIAL REGISTRATION NUMBER

UMIN000033276; Pre-results.

A simple model of mechanical effects to estimate metabolic cost of human walking

Since the advent of energy measurement devices, gait experiments have shown that energetic economy has a large influence on human walking behavior. However, few cost models have attempted to capture the major energy components under comprehensive walking conditions. Here we present a simple but unified model that uses walking mechanics to estimate metabolic cost at different speeds and step lengths and for six other biomechanically-relevant gait experiments in literature. This includes at various gait postures (e.g. extra foot lift), anthropometric dimensions (e.g. added mass), and reduced gravity conditions, without the need for parameter tuning to design new gait trajectories. Our results suggest that the metabolic cost of walking can largely be explained by the linear combination of four costs-swing and torso dynamics, center of mass velocity redirection, ground clearance, and body weight support. The overall energetic cost is a tradeoff among these separable components, shaped by how they manifest under different walking conditions.

Estimating the value of life and injury for pedestrians using a stated preference framework

INTRODUCTION

The incidence of pedestrian death over the period 2010 to 2014 per 1000,000 in North Cyprus is about 2.5 times that of the EU, with 10.5 times more pedestrian road injuries than deaths. With the prospect of North Cyprus entering the EU, many investments need to be undertaken to improve road safety in order to reach EU benchmarks.

METHOD

We conducted a stated choice experiment to identify the preferences and tradeoffs of pedestrians in North Cyprus for improved walking times, pedestrian costs, and safety. The choice of route was examined using mixed logit models to obtain the marginal utilities associated with each attribute of the routes that consumers chose. These were used to estimate the individuals' willingness to pay (WTP) to save walking time and to avoid pedestrian fatalities and injuries. We then used the results to obtain community-wide estimates of the value of a statistical life (VSL) saved, the value of an injury (VI) prevented, and the value per hour of walking time saved.

RESULTS

The estimate of the VSL was €699,434 and the estimate of VI was €20,077. These values are consistent, after adjusting for differences in incomes, with the median results of similar studies done for EU countries. The estimated value of time to pedestrians is €7.20 per person hour.

CONCLUSIONS

The ratio of deaths to injuries is much higher for pedestrians than for road accidents, and this is completely consistent with the higher estimated WTP to avoid a pedestrian accident than to avoid a car accident. The value of time of €7.20 is quite high relative to the wages earned.

PRACTICAL APPLICATIONS

Findings provide a set of information on the VRR for fatalities and injuries and the value of pedestrian time that is critical for conducing ex ante appraisals of investments to improve pedestrian safety.

The role of the built environment in explaining educational inequalities in walking and cycling among adults in the Netherlands

BACKGROUND

This study examined whether characteristics of the residential built environment (i.e. population density, level of mixed land use, connectivity, accessibility of facilities, accessibility of green) contributed to educational inequalities in walking and cycling among adults.

METHODS

Data from participants (32-82 years) of the 2011 survey of the Dutch population-based GLOBE study were used (N = 2375). Highest attained educational level (independent variable) and walking for transport, cycling for transport, walking in leisure time and cycling in leisure time (dependent variables) were self-reported in the survey. GIS-systems were used to obtain spatial data on residential built environment characteristics. A four-step mediation-based analysis with log-linear regression models was used to examine to contribution of the residential built environment to educational inequalities in walking and cycling.

RESULTS

As compared to the lowest educational group, the highest educational group was more likely to cycle for transport (RR 1.13, 95% CI 1.04-1.23), walk in leisure time (RR 1.12, 95% CI 1.04-1.21), and cycle in leisure time (RR 1.12, 95% CI 1.03-1.22). Objective built environment characteristics were related to these outcomes, but contributed minimally to educational inequalities in walking and cycling. On the other hand, compared to the lowest educational group, the highest educational group was less likely to walk for transport (RR 0.91, 95% CI 0.82-1.01), which could partly be attributed to differences in the built environment.

CONCLUSION

This study found that objective built environment characteristics contributed minimally to educational inequalities in walking and cycling in the Netherlands.

Comparison of the HUI3 and the EQ-5D-3L in a nursing home setting

BACKGROUND

Accurately assessing changes in the quality of life of older people living permanently in nursing homes is important. The multi-attribute utility instrument most commonly used and recommended to assess health-related quality of life in the nursing home population is the three-level EuroQol EQ-5D-3L. To date, there have been no studies using the Health Utilities Index Mark III (HUI3). The purpose of this study was to compare the level of agreement and sensitivity to change of the EQ-5D-3L and HUI3 in a nursing home population.

METHODS

EQ-5D-3L and HUI3 scores were measured as part of a cluster randomised controlled trial of nurse led care coordination in a nursing home population in Perth, Western Australia at baseline and 6-month follow up.

RESULTS

Both measures were completed for 199 residents at baseline and 177 at 6-month follow-up. Mean baseline utility scores for EQ-5D-3L (0.45; 95% CI 0.41-0.49) and HUI3 (0.15; 95% CI 0.10-0.20) were significantly different (Wilcoxon signed rank test, p<0.01) and agreement was poor to moderate between absolute scores from each instrument (intra-class correlation coefficient = 0.63). The EQ-5D-3L appeared more sensitive to change over the 6-month period.

CONCLUSION

Our findings show that the EQ-5D-3L and HUI3 estimate different utility scores among nursing home residents. These differences should be taken into account, particularly when considering the implications of the cost-effectiveness of particular interventions and we conclude that the HUI3 is no better suited to measuring health-related quality of life in a nursing home population when compared to the EQ-5D-3L.

Analysis of pedestrian accident costs in Sudan using the willingness-to-pay method

The willingness-to-pay (WTP) with contingent valuation (CV) method has been proven to be a valid tool for the valuation of non-market goods or socio-economic costs of road traffic accidents among communities in developed and developing countries. Research on accident costing tends to estimate the value of statistical life (VOSL) for all road users by providing a principle for the evaluation of road safety interventions in cost-benefit analysis. As in many other developing countries, the economic loss of traffic accidents in Sudan is noticeable; however, analytical research to estimate the magnitude and impact of that loss is lacking. Reports have shown that pedestrians account for more than 40% of the total number of fatalities. In this study, the WTP-CV approach was used to determine the amount of money that pedestrians in Sudan are willing to pay to reduce the risk of their own death. The impact of the socioeconomic factors, risk levels, and walking behaviors of pedestrians on their WTP for fatality risk reduction was also evaluated. Data were collected from two cities-Khartoum and Nyala-using a survey questionnaire that included 1400 respondents. The WTP-CV Payment Card Questionnaire was designed to ensure that Sudan pedestrians can easily determine the amount of money that would be required to reduce the fatality risk from a pedestrian-related accident. The analysis results show that the estimated VOSL for Sudanese pedestrians ranges from US$0.019 to US$0.101 million. In addition, the willingness-to-pay by Sudanese pedestrians to reduce their fatality risk tends to increase with age, household income, educational level, safety perception, and average time spent on social activities with family and community.

Associations of neighborhood characteristics with active park use: an observational study in two cities in the USA and Belgium

BACKGROUND

Public parks can be an important setting for physical activity promotion, but to increase park use and the activity levels of park users, the crucial attributes related to active park use need to be defined. Not only user characteristics and structural park attributes, but also characteristics of the surrounding neighborhood are important to examine. Furthermore, internationally comparable studies are needed, to find out if similar intervention strategies might be effective worldwide. The main aim of this study was to examine whether the overall number of park visitors and their activity levels depend on study site, neighborhood walkability and neighborhood income.

METHODS

Data were collected in 20 parks in Ghent, Belgium and San Diego, USA. Two trained observers systematically coded park characteristics using the Environmental Assessment of Public Recreation Spaces (EAPRS) tool, and park user characteristics using the System for Observing Play and recreation in Communities (SOPARC) tool. Multilevel multiple regression models were conducted in MLwiN 2.25.

RESULTS

In San Diego parks, activity levels of park visitors and number of vigorously active visitors were higher than in Ghent, while the number of visitors walking and the overall number of park visitors were lower. Neighborhood walkability was positively associated with the overall number of visitors, the number of visitors walking, number of sedentary visitors and mean activity levels of visitors. Neighborhood income was positively associated with the overall number of visitors, but negatively with the number of visitors being vigorously active.

CONCLUSIONS

Neighborhood characteristics are important to explain park use. Neighborhood walkability-related attributes should be taken into account when promoting the use of existing parks or creating new parks. Because no strong differences were found between parks in high- and low-income neighborhoods, it seems that promoting park use might be a promising strategy to increase physical activity in low-income populations, known to be at higher risk for overweight and obesity.

Financial incentives to promote active travel: an evidence review and economic framework

CONTEXT

Financial incentives, including taxes and subsidies, can be used to encourage behavior change. They are common in transport policy for tackling externalities associated with use of motor vehicles, and in public health for influencing alcohol consumption and smoking behaviors. Financial incentives also offer policymakers a compromise between "nudging," which may be insufficient for changing habitual behavior, and regulations that restrict individual choice.

EVIDENCE ACQUISITION

The literature review identified studies published between January 1997 and January 2012 of financial incentives relating to any mode of travel in which the impact on active travel, physical activity, or obesity levels was reported. It encompassed macroenvironmental schemes, such as gasoline taxes, and microenvironmental schemes, such as employer-subsidized bicycles. Five relevant reviews and 20 primary studies (of which nine were not included in the reviews) were identified.

EVIDENCE SYNTHESIS

The results show that more-robust evidence is required if policymakers are to maximize the health impact of fiscal policy relating to transport schemes of this kind.

CONCLUSIONS

Drawing on a literature review and insights from the SLOTH (sleep, leisure, occupation, transportation, and home-based activities) time-budget model, this paper argues that financial incentives may have a larger role in promoting walking and cycling than is acknowledged generally.

Effect of increasing active travel in urban England and Wales on costs to the National Health Service

Increased walking and cycling in urban areas and reduced use of private cars could have positive effects on many health outcomes. We estimated the potential effect of increased walking and cycling in urban England and Wales on costs to the National Health Service (NHS) for seven diseases--namely, type 2 diabetes, dementia, cerebrovascular disease, breast cancer, colorectal cancer, depression, and ischaemic heart disease--that are associated with physical inactivity. Within 20 years, reductions in the prevalences of type 2 diabetes, dementia, ischaemic heart disease, cerebrovascular disease, and cancer because of increased physical activity would lead to savings of roughly UK£17 billion (in 2010 prices) for the NHS, after adjustment for an increased risk of road traffic injuries. Further costs would be averted after 20 years. Sensitivity analyses show that results are invariably positive but sensitive to assumptions about time lag between the increase in active travel and changes in health outcomes. Increasing the amount of walking and cycling in urban settings could reduce costs to the NHS, permitting decreased government expenditure on health or releasing resources to fund additional health care.

Exploring patterns of movement suspension in pedestrian mobility

One of the main tasks in analyzing pedestrian movement is to detect places where pedestrians stop, as those places usually are associated with specific human activities, and they can allow us to understand pedestrian movement behavior. Very few approaches have been proposed to detect the locations of stops in positioning data sets, and they often are based on selecting the location of candidate stops as well as potential spatial and temporal thresholds according to different application requirements. However, these approaches are not suitable for analyzing the slow movement of pedestrians where the inaccuracy of a nondifferential global positioning system commonly used for movement tracking is so significant that it can hinder the selection of adequate thresholds. In this article, we propose an exploratory statistical approach to detect patterns of movement suspension using a local indicator of spatial association (LISA) in a vector space representation. Two different positioning data sets are used to evaluate our approach in terms of exploring movement suspension patterns that can be related to different landscapes: players of an urban outdoor mobile game and visitors of a natural park. The results of both experiments show that patterns of movement suspension were located at places such as checkpoints in the game and different attractions and facilities in the park. Based on these results, we conclude that using LISA is a reliable approach for exploring movement suspension patterns that represent the places where the movement of pedestrians is temporally suspended by physical restrictions (e.g., checkpoints of a mobile game and the route choosing points of a park).

Where is the café? The challenge of making retail uses viable in mixed-use suburban developments

Contemporary planners see mixing residential, retail and other compatible uses as an essential planning principle. This paper explores the challenges that planners, developers and municipal councillors encounter in trying to implement retail uses as part of the mix in suburban areas in three Canadian cities. The study finds that planners employ evolutionary theories of urban development to naturalise their normative visions of walkable and sociable communities. By contrast, developers point to consumer behaviour to explain why planners' ideas on mix do not work. In a society where people shop at big-box outlets, making the local café or pub commercially viable proves increasingly challenging.

Retrofitting the suburbs to increase walking: evidence from a land-use-travel study

This paper reports results from a detailed travel diary survey of 2125 residents in the South Bay area of Los Angeles County - a mature, auto-oriented suburban region. Study areas were divided into four centres, typical of compact development or smart growth, and four linear, auto-oriented corridors. Results show substantial variation in the amount of walking across study areas. Trips are shorter and more likely to be via walking in centres. A key to the centres' increased walking travel is the concentration of local shopping and service destinations in a commercial core. Yet the amount of business concentration that is associated with highly pedestrian-oriented neighbourhoods is from three to four times as large as what can be supported by the local resident base, suggesting that pedestrian-oriented neighbourhoods necessarily import shopping trips, and hence driving trips, from larger surrounding catchment areas. The results suggest both land use and mobility strategies that can be appropriate for suburban regions.

A silver lining? The connection between gasoline prices and obesity

I find evidence of a negative association between gasoline prices and body weight using a fixed effects model with several robustness checks. I also show that increases in gas prices are associated with additional walking and a reduction in the frequency with which people eat at restaurants, explaining their effect on weight. My estimates imply that 8% of the rise in obesity between 1979 and 2004 can be attributed to the concurrent drop in real gas prices, and that a permanent $1 increase in gasoline prices would reduce overweight and obesity in the United States by 7% and 10%.

The impact of transit-oriented development on housing prices in San Diego, CA

This research measures the influence of transit-oriented development (TOD) on the San Diego, CA, condominium market. Many view TOD as a key element in creating a less auto dependent and more sustainable transport system. Price premiums indicate a potential for a market-driven expansion of TOD inventory. A hedonic price model is estimated to isolate statistically the effect of TOD. This includes interaction terms between station distance and various measures of pedestrian orientation. The resulting model shows that station proximity has a significantly stronger impact when coupled with a pedestrian-oriented environment. Conversely, station area condominiums in more auto-oriented environments may sell at a discount. This indicates that TOD has a synergistic value greater than the sum of its parts. It also implies a healthy demand for more TOD housing in San Diego.

The epidemic of pediatric traffic injuries in South Florida: a review of the problem and initial results of a prospective surveillance strategy

This study identified specific regional risk factors for the high rate of pediatric pedestrian trauma in Florida. Of the 29 cases studied prospectively, 3 (10%) occurred near ice cream trucks and 13 (45%) involved "dart-outs"; mean hospital charges were 24,478 +/- 43,939 US dollars. Recommendations included an engineering change for a dangerous intersection, and a population-based recommendation was to equip ice cream trucks with extending stop signs.

Wildfire effects on hiking and biking demand in New Mexico: a travel cost study

We use a travel cost model to test the effects of wild and prescribed fire on visitation by hikers and mountain bikers in New Mexico. Our results indicate that net benefits for mountain bikers is $150 per trip and that they take an average of 6.2 trips per year. Hikers take 2.8 trips per year with individual net benefits per trip of $130. Both hikers' and mountain bikers' demand functions react adversely to prescribed burning. Net benefits for both groups fall as areas recover from prescribed burns. Because both visitation and annual recreation benefits decrease to these two types of visitors, this gives rise to multiple use costs associated with prescribed burning. With respect to wildfire, hikers and mountain bikers both exhibit decreased visitation as areas recover from wildfires, however, only hikers indicate an increase in per trip net benefits. Bikers' demand effectively drops to zero. These results differ from previous findings in the literature and have implications for efficient implementation of the National Fire Plan and whether prescribed burning is a cost effective tool for multiple use management of National Forests. Specifically, that fire and recreation managers cannot expect recreation users to react similarly to fire across recreation activities, or different geographic regions. What is cost effective in one region may not be so in another.

Pathways of disadvantage? Walking as a mode of transport among low-income mothers

Research shows that lack of car ownership is associated with poorer health. It is often assumed that the reason for this observed relationship is that access to a car--or not--reflects access to household assets. Consequently, lack of car ownership is used as a standard marker of low socio-economic status. However, little attention has been paid to the experience of carlessness in the context of disadvantaged lives. This paper argues that "no access to a car" is not only an indicator of low socio-economic status but of walking as a mode of transport. These arguments are illustrated by data from a study of 30 low-income mothers with young children. Although walking is promoted as both an excellent and inexpensive form of exercise, these data suggest that reliance on walking can have negative effects on the welfare of families. The paper draws on qualitative data to describe the ways in which carlessness restricts access to health and social care resources such as food shops, health-care services and social networks. It also explores the impact of walking on the well being of mothers and their day-to-day relationships with children. This is compounded by walking through areas that are neglected and depressed. The paper concludes that strategies to reduce social exclusion must recognise the contradictory health effects of walking and aim to regenerate the physical fabric of social housing estates as well as improve public transport options.

Which are the relevant costs and benefits of road safety measures designed for pedestrians and cyclists?

This paper discusses the current state-of-the-art with respect to impact assessment and cost-benefit analysis of measures designed to improve safety or mobility for pedestrians and cyclists. The study concludes that a number of impacts that are likely to regarded as important for pedestrians and cyclists are not included in current impact assessments and cost-benefit analyses as these are made in Norway. Impacts that are not currently included in impact assessments and cost-benefit analyses are: (a) changes in the amount of walking and cycling; (b) changes in travel time for pedestrians and cyclists; (c) changes in road user insecurity (feeling of safety); and (d) changes in road user health state. In order to include these effects in impact assessments and cost-benefit analyses, more needs to be known about their occurrence and monetary value. Hypothetical examples of ideally designed cost-benefit analyses are given, based on highly preliminary monetary values for travel time, insecurity and generalised costs of travel for pedestrians and cyclists. These analyses indicate that inclusion of these effects in cost-benefit analyses could make a major difference for the results of those analyses.

Cost-benefit analysis of walking to prevent coronary heart disease

OBJECTIVE

To quantify the cost-benefit relationship of walking to prevent coronary heart disease.

DESIGN

Cost-benefit analysis.

PARTICIPANTS

Hypothetical cohorts of sedentary men and women aged 35 to 74 years.

MAIN OUTCOME MEASURES

Decision-analysis simulation was used to evaluate the cost-benefit relationship of walking, varying level of benefit from exercise, frequency of exercise to achieve benefit, participation rates, and costs of exercise and injury.

RESULTS

At a relative risk of 1.9 for heart disease associated with sedentary behavior, $5.6 billion would be saved annually if 10% of adults began a regular walking program. A $4.3 billion savings is predicted if the entire sedentary population began walking regularly and the cost of the time an individual spends exercising is accounted for in those who dislike exercising. According to our baseline assumptions, walking is economically beneficial for men aged 35 to 64 years and for women aged 55 to 64 years. The threshold of relative risk at which economic benefit is found for walking in this population overall is estimated at 1.7, and under a volunteer model, most adults would benefit even at a relative risk of 1.15.

CONCLUSIONS

There are significant sex and age differences in the economic benefits of walking to prevent heart disease. The value assigned to the time an individual spends exercising has a significant impact on the results. Overall, a substantial savings is predicted from encouraging sedentary individuals to participate in a regular walking program.