Health impacts of the Cambridgeshire Guided Busway: a natural experimental study

Parents' perceived barriers to active commuting to school. Comparative study between Spanish and Ecuadorian cities

Parents´ perceptions can influence their children´s mode of commuting to school. In this sense, the purposes of this study were to compare parental barriers towards active commuting to school (ACS) between Ecuadorian and Spanish children, and to analyze the associations between those barriers and the children's mode of commuting. Descriptive and comparative analyses were performed using Chi-square and T-student test. Associations were analyzed by several logistic regression models. Results showed that road safety is the main barrier for ACS, and that all the barriers are perceived as higher by Ecuadorian parents (p<0.001). It was also found that Ecuadorian children were less likely to be active when parents perceive greater total barriers (OR=0.15, CI=0.06, 0.40). Public policies should focus on reducing the parental barriers in order to increase ACS, specifically those related to road safety.

Wellbeing Impact Study of High-Speed 2 (WISH2): Protocol for a mixed-methods examination of the impact of major transport infrastructure development on mental health and wellbeing

Although research has demonstrated that transport infrastructure development can have positive and negative health-related impacts, most of this research has not considered mental health and wellbeing separately from physical health. There is also limited understanding of whether and how any effects might be experienced differently across population groups, whether this differs according to the stage of development (e.g. planning, construction), and how changes to planned infrastructure may affect mental health and wellbeing. This paper presents a protocol for the Wellbeing Impact Study of HS2 (WISH2), which seeks to address these questions using a high-speed rail development in the UK as an applied example. WISH2 is a 10-year, integrated, longitudinal, mixed-methods project using general practices (primary medical care providers in the UK) as an avenue for participant recruitment and for providing a geographically defined population for which aggregated data on mental health indicators are available. The research comprises: (i) a combined longitudinal and repeated cross-sectional cohort study involving multiple waves of survey data collection and data from medical records; (ii) longitudinal, semi-structured interviews and focus groups with residents and community stakeholders from exposed areas; (iii) analysis of administrative data aggregated at the general practice population level; and (iv) health economic analysis of mental health and wellbeing impacts. The study findings will support the development of strategies to reduce negative impacts and/or enhance positive mental health and wellbeing impacts of high-speed rail developments and other large-scale infrastructure projects.

Changing mobility practices. Can meta-ethnography inform transferable and policy-relevant theory?

Social practice theories have attracted attention for their potential insights into how to change transport systems towards "healthier" states. However, most evidence is from small-scale qualitative case studies. We explored whether a synthesis of qualitative evidence on mobility practices in one country, informed by meta-ethnography and a Bourdieusian approach to practice, could produce theory that is of sufficient abstraction to be transferable, yet also capable of informing intervention planning. The synthesis identified three third order constructs: mobility practices result from habitus plus capital in fields; specific configurations of local mobility practices are shaped, but not determined, by material infrastructures and social structures; and changes in practice happen across a number of scales and temporalities. This body of evidence as a whole was then interpreted as an integrative "storyline": Mobility systems are complex, in that outcomes from interventions are neither unilinear nor necessarily predictable from aggregations of individual practice changes. Infrastructure changes may be a necessary, but not sufficient, condition for change. Moving systems towards "healthier" states requires changing habitus such that "healthier" practices align with fields, and that interventions take sufficient account of the power relations that materially and symbolically constrain or enable attachments to and changes in mobility practices. Meta-ethnography is a useful approach for integrating qualitative evidence for informing policy.

Impact of structural-level environmental interventions on physical activity: a systematic review

OBJECTIVE

To determine the effectiveness of structural-level environmental interventions on the changes in PA levels in the populations examined.

METHODS

Natural experiments that involve environmental intervention with structural modification were included. The primary outcome PA levels with consideration of both objective and subjective measurements. An electronic search was carried out in Medline/Pubmed, SCIENCE DIRECT, WEB OF SCIENCE, and CINAHL up to January 2022. Two reviewers screened titles and abstracts, selected studies, extracted relevant data, and examined study quality. A qualitative synthesis was performed.

RESULTS

Twenty-six articles were included. The structural-level environmental interventions included 4 fundamental areas: schools, work environments, streets or cities, and neighborhoods or parks. Of the 26 studies, 21 examined outdoor environments like parks, cities, pedestrian walkways, or steps, while 5 examined indoor or closed environments like schools and workplaces revealing that structural-level environmental interventions improve PA levels with the greatest effect in parks and active transportation. A risk of bias is inherent in natural experiments which is a limitation of this study. In schools and work areas, there is evidence of both decrease in sedentary time and an increase in PA related to environmental modifications.

CONCLUSION

Structural-level environmental modifications in parks and active transportation demonstrated greater effects in promoting PA. Environmental modifications can impact physical activity in the population. Given that the economic and cultural setting is a key variable when considering the effectiveness of structural interventions, and since only 1 of the 26 reviewed articles included such data, more studies examining economic factors are needed especially in low- and middle-income countries like in South America.

TRIAL REGISTRATION

PROSPERO CRD42021229718.

Assessing Park Accessibility Based on a Dynamic Huff Two-Step Floating Catchment Area Method and Map Service API

Park green space (PGS) is an important part of urban ecosystem and green infrastructure, and the ease of access to PGS is closely related to the health of residents. A growing number of studies have attempted to identify accessibility disparities, but results have varied because of the travel mode choice and the measurement method. This study proposes a dynamic Huff two-step floating catchment area (H2SFCA) method based on map service API (Application Programming Interface) to assess the accessibility of PGS, with the Gini coefficient and bivariate local Moran’s I used to analyze accessibility equity. Results show that: (1) driving and biking modes have more significant spatiotemporal compression effects than dynamic modes, public transit, and walking mode. (2) The accessibility values and spatial patterns vary significantly by travel mode. The PGS availability pattern at the local level is more uneven than the distribution of accessibility at the regional level. In comparison with dynamic travel modes, the accessibility values for the single travel mode are more likely to be overestimated or underestimated. (3) The PGS accessibility by the dynamic modes generally has better spatial equity and residents can select suitable travel tools to acquire more equitable park services. In addition, there is a significant accessibility difference between dynamic driving-based mode and dynamic transit-based mode in four subdistricts, which are mainly located in the south of Tianhe District. The public transport facilities linking parks in these areas need to be optimized. This study further improves the accessibility evaluation method, with the findings conducive to the implementation of refined PGS planning and management.

Metro and elderly health in Hong Kong: protocol for a natural experiment study in a high-density city

INTRODUCTION

Public transport accessible to older people may offer a transformative solution to achieving healthy ageing. However, the evidence to support such transport infrastructure modifications is unclear. Previous studies on public transport use and elderly health were mostly observational studies using cross-sectional data. Few studies have examined the before-and-after effects of a new metro, for example, to see if it leads to improved elderly health.

METHODS AND ANALYSIS

We use a new metro line in Hong Kong as a natural experiment to examine the impact of the metro-led public transport intervention on elderly health. In Hong Kong, more than 90% of daily travels are made by public transport. The public transport modifications consist of the new metro line with eight stations and changes in the walking environment and bus services around the stations. We will look at the before-and-after differences in public transport use and health outcomes between elderly participants living in treatment neighbourhoods (400 m walking buffered areas of the new metro stations) and in control groups (living in comparable areas but unaffected by the new metro). Questionnaire-based baseline data were collected in 2019 before the COVID-19 pandemic, while some qualitative interviews are ongoing. Amid the pandemic, we conducted a quick telephone-based survey of COVID-19's potential impact on public transport use behaviours of our elderly cohort in September 2020. Note there is no lockdown in Hong Kong until the writing of the paper (January 2021). After the new metro opens, we will conduct a follow-up survey, tentatively in late 2022. We aim to investigate if the new metro and the associated changes in the built environment have any effects on public transport use behaviours, physical activity and wider health outcomes among the elderly (eg, social inclusion, quality of life, subjective well-being).

ETHICS AND DISSEMINATION

The Human Research Ethics Committee of the University of Hong Kong reviewed and approved the study procedures and materials (reference number: EA1710040). Results will be communicated through scientific papers and research reports.

Interventions Aiming to Promote Active Commuting in Children and Adolescents: An Evaluation From a Sex/Gender Perspective

Active commuting (AC) provides numerous health benefits and is one way to improve physical activity in children and adolescents. Boys are more likely to use active transport modes than girls. Girls and boys benefit differently from interventions that promote AC. The aim of this systematic review is to evaluate the effects of interventions on girls and boys and to appraise the extent to which previous studies have taken sex/gender into account. Eleven electronic databases were searched to identify all relevant randomized and non-randomized controlled trials based on a priori defined eligibility criteria. Two independent reviewers screened the literature for eligibility and assessed risk of bias. Semiquantitative analyses were conducted to evaluate the effects of intervention effects by taking sex/gender aspects into account. To evaluate sex/gender considerations in interventional studies, a recently developed sex/gender checklist was applied. Twelve studies were included that examined intervention effects on AC in girls and boys. Three intervention studies showed significant effects in increasing AC, with one study favoring girls, one favoring boys, and another focusing on a single sex/gender (only girls). According to the checklist, the overall sex/gender rating highlighted a lack of information in sex/gender consideration. Studies with and without significant effects indicated no differences in the sex/gender checklist. The results indicate that sex/gender is not considered adequately in primary interventional research on AC. To evaluate the effectiveness of intervention in boys and girls, detailed analyses of sex/gender are required, and better reporting about sex/gender-specific intervention content is necessary. In future health research to promote AC, sex/gender should be systematically taken into account.

Effect of Major Life Events on Travel Behaviours: A Scoping Review

The transportation sector accounts for about a quarter of global greenhouse gas emissions. Previous research suggests that major life events may be “windows of opportunity” for travel behaviour change. Our scoping review examined the effects of seven events (transitions to secondary school, post-secondary studies, labour market, marriage, parenthood, retirement, and relocation) on travel behaviours. Five databases were searched (MEDLINE, APA PsycINFO, Web of Science, SportDISCUS, and ProQuest Dissertations and Theses) and 80 articles met inclusion criteria. Relocation was the most commonly examined event (with 51 studies). Findings illustrate that moving to compact neighbourhoods (with shorter commute distance/travel time, greater walkability/access to destinations) was associated with shifts towards sustainable travel modes (e.g., walking, cycling, and transit). Relocation might be particularly conducive to implementing scalable sustainable transportation interventions, as all six interventions with appropriate statistical power were effective. Entry into the labour market was generally associated with increased car use and declines in sustainable transportation. Qualitative studies suggested that attitudes towards cycling may become negative during adolescence, while attitudes towards driving improve, highlighting a need for concerted action. Evidence for other events was less consistent. Research in developing countries remain scarce and further intervention research is needed to enhance quality of evidence.

The social and physical workplace environment and commute mode: A natural experimental study

Despite strong evidence for health benefits from active travel, levels remain low in many countries. Changes to the physical and social workplace environment might encourage active travel but evaluation has been limited. We explored associations between changes in the physical and social workplace environment and changes in commute mode over one year among 419 participants in the Commuting and Health in Cambridge study. In adjusted analyses, an increase in the presence of one physical characteristic (e.g. bicycle parking or shower facilities) was associated with a 3.3% (95% confidence interval 1.0-5.6) reduction in the proportion of commutes by private motor vehicle and a 4.4% (95% CI 1.2-7.7) increase in the proportion of trips including active modes among men. These associations were not seen in women. A change to a more favourable social environment for walking or cycling among workplace management was associated with an increased proportion of commutes including active modes in women (4.5%, 95% CI 1.4-7.5) but not men. However, in both genders a change to more a favourable social environment for cycling among colleagues was associated with a reduced proportion of commutes by exclusively active modes (-2.8%, 95% CI -5.0 to -0.6). This study provides longitudinal evidence for gender differences in the associations between workplace environment and commute mode. A more supportive physical environment was associated with more active commuting in men, while the social environment appeared to have more complex associations that were stronger among women.

Physical activity accrued as part of public transport use in England

BACKGROUND

Walking and cycling for transport (active travel) is an important source of physical activity with established health benefits. However, levels of physical activity accrued during public transport journeys in England are unknown.

METHODS

Using the English National Travel Survey 2010-14 we quantified active travel as part of public transport journeys. Linear regression models compared levels of physical activity across public transport modes, and logistic regression models compared the odds of undertaking 30 min a day of physical activity.

RESULTS

Public transport users accumulated 20.5 min (95% confidence interval=19.8, 21.2) a day of physical activity as part of public transport journeys. Train users accumulated 28.1 min (26.3, 30.0) with bus users 16.0 min (15.3, 16.8). Overall, 34% (32%, 36%) of public transport users achieved 30 min a day of physical activity in the course of their journeys; 21% (19%, 24%) of bus users and 52% (47%, 56%) of train users.

CONCLUSION

Public transport use is an effective way to incorporate physical activity into daily life. One in three public transport users meet physical activity guidelines suggesting that shifts from sedentary travel modes to public transport could dramatically raise the proportion of populations achieving recommended levels of physical activity.

New metro system and active travel: A natural experiment

BACKGROUND

We used the first metro system in a developing city as a natural experiment to investigate the causal inference in the new metro's impact on modal shift and active travel.

MATERIAL AND METHODS

The treatment group was formed by residents from neighbourhoods located within the 800-m walking distance to new metro stations. The first control group was formed by residents lived 1.6 km away from and outside of walking distance to the nearest station, and the second was 5 km away and outside of cycling distance. The groups were determined by local transit-oriented planning practice and empirical studies on active travel. Of the 5627 participants who had finished a baseline travel behaviour survey before new metro launched, 1770 returned and completed the follow-up survey a year after the metro's operation, which consists of 833 cohort participants in the treatment group and 937 in the two types of control groups. We used a difference-in-difference method to make before and after comparisons of travel behaviour changes between treatment and control groups.

RESULTS

Our longitudinal data analyses revealed diverse travel behaviour changes. In general, people who used to take bus have adopted metro. The average metro usage was 30.9 (28.8-33.3) minutes daily for work trips and 16.6 (14.9-18.7) minutes daily for non-work trips. Walking time decreased 19.7 minutes at most (p < 0.001), and cycling decreased 22.1 minutes daily (p < 0.001). Car and e-bike usages remained largely unchanged before and after new metro, without difference between treatment and control groups.

CONCLUSION

The natural experiment study provided the first empirical evidence in a developing city context on causal inference in new metro's impact on active travel. A new metro does not necessarily promote active travel increase or car use reduction, calling for caution in making general assumptions about the effects of urban rail transit investments. We suggest local urban and transport planning knowledge could be useful in designing and explaining the complex natural experiments in transport and health.

The atmospheric impacts of initiatives advancing shifts towards low-emission mobility: A scoping review

In an urban environment, people's daily traffic choices are reflected in emissions and the resulting local air composition, or air quality. Traffic contributes to the emissions of both carbon dioxide (CO2), affecting climate, and particulate matter (PM), affecting atmospheric chemistry and human health. While the development of city infrastructure is not in the hands of individuals, it is their transport mode choices that constitute traffic. In this scoping review we analyse 108 initiatives from around the world potentially influencing individual travel behaviour and producing changes in the shares of different transport modes (modal shifts). The targets, types and techniques of initiatives are identified. Examples of economic, regulative, structural and persuasive initiatives are included. Special focus is on whether the impacts on CO2 emissions, PM emissions and/or PM concentrations have been quantitatively evaluated, and on the quality and results of the evaluations. We observe that a variety of targets can motivate actions that lead to modal shifts and emission reductions. The results indicate that the level of atmospheric evaluations is low: absolute or relative changes in emissions and/or concentrations had been evaluated for only 31% (N = 34) of the reviewed initiatives, with substantial heterogeneity in quality. Sanctions, such as congestion charge and restrictions, have more likely been evaluated in peer reviewed analyses than incentives. Scientific evaluations of impacts on ambient PM concentrations are especially scarce (N = 4), although Air Quality is the primary target of 13% of actions and secondary target for at least 12%. We discuss the determinants of success and failure, when it comes to different types of initiatives, emission reductions and evaluations. A high-quality evaluation of atmospheric impacts captures the following: correct data about the modal shift (rate and direction), exclusion of external factors affecting the shift and emissions, and possible indirect impacts of the shift.

Physical Activity Levels and New Public Transit: A Systematic Review and Meta-analysis

CONTEXT

Physical inactivity is a public health concern as it contributes to the rising burden of noncommunicable diseases. Introducing new public transportation options, such as extending or building new light rail or bus rapid transit stations, could encourage commuters to walk to and from public transit stops, thus increasing their physical activity levels. Despite previous research generally finding positive associations between public transit usage and physical activity levels, few have summarized the association between introducing new public transportation options and different intensities of physical activity. This study aimed to systematically review the current evidence and perform a meta-analysis on this association.

EVIDENCE ACQUISITION

Ten databases were systematically searched for studies published between 1997 and 2017. To ensure comparability, study outcomes were converted to MET hours/week. A random effects meta-analysis and sensitivity analysis were then conducted.

EVIDENCE SYNTHESIS

Nine studies were identified to be included in the systematic review, of which five were eligible for meta-analysis. Pooled results suggest that building new public transit options is associated with a statistically significant increase in light to moderate physical activity levels by 1.76 MET hours/week (95% CI=0.19, 3.32, p=0.03). This is equivalent to increasing walking and other light to moderate physical activity by about 30 minutes per week, relative to baseline. No significant effect was found for the moderate to vigorous physical activity outcome.

CONCLUSIONS

Results show new public transit options can substantially contribute to increasing low- to moderate-intensity exercise levels, which has the potential to improve health on a population scale.

The effects of changes to the built environment on the mental health and well-being of adults: Systematic review

There is increasing interest in the influence of place on health, and the need to distinguish between environmental and individual level factors. For environmental-level factors, current evidence tends to show associations through cross-sectional and uncontrolled longitudinal analyses rather than through more robust study designs that can provide stronger causal evidence. We restricted this systematic review to randomised (or cluster) randomised controlled trials and controlled before-and-after studies of changes to the built environment. Date of search was December 2016. We identified 14 studies. No evidence was found of an effect on mental health from 'urban regeneration' and 'improving green infrastructure' studies. Beneficial effects on quality-of-life outcomes from 'improving green infrastructure' were found in two studies. One 'improving green infrastructure' study reported an improvement in social isolation. Risk-of-bias assessment indicated robust data from only four studies. Overall, evidence for the impact of built environment interventions on mental health and quality-of-life is weak. Future research requires more robust study designs and interdisciplinary research involving public health, planning and urban design experts.

Effects of urban motorways on physical activity and sedentary behaviour in local residents: a natural experimental study

BACKGROUND

There is little evidence on how changing the physical environment changes health-related behaviours. We studied the effects of the new M74 motorway (freeway) - opened in 2011 - and the existing M8 motorway in Glasgow, Scotland, on physical activity and sedentary behaviour among local residents.

METHODS

This natural experimental study used baseline (T1; 2005) and follow-up data (T2; 2013) from a longitudinal cohort (N = 365) and two cross-sectional samples (T1 N = 980; T2 N = 978). Adult participants were recruited from three study areas: one surrounding the new motorway, one surrounding the existing motorway, and a third, control, area without a motorway. The outcomes were self-reported time spent sitting, walking, and in moderate-to-vigorous physical activity (MVPA). Motorway exposure was defined in terms of (1) study area and (2) distance from home to the nearest motorway junction. Outcomes were regressed on exposures in two-part (walking and MVPA) or linear (sedentary behaviour) cohort and repeat cross-sectional models, adjusted for baseline behaviour and sociodemographic covariates.

RESULTS

Cohort participants living in the M8 area were less likely to participate in MVPA at follow-up than those living in the area without a motorway (OR 0.37; 95%CI 0.15, 0.91). Within the M8 area, those living closer to the motorway were also less likely to do so (OR 0.30; 95%CI 0.09, 0.97). No other statistically significant results were found.

CONCLUSIONS

We found some evidence of a negative association between exposure to an existing urban motorway and MVPA. However, the behavioural impacts of motorways are likely to be complex and evolve over time.

Negotiating multisectoral evidence: a qualitative study of knowledge exchange at the intersection of transport and public health

Background

For the prevention and control of chronic diseases, two strategies are frequently highlighted: that public health should be evidence based, and that it should develop a multisectoral approach. At the end of a natural experimental study of the health impacts of new transport infrastructure, we took the opportunity of a knowledge exchange forum to explore how stakeholders assessed, negotiated and intended to apply multisectoral evidence in policy and practice at the intersection of transport and health. We aimed to better understand the challenges they faced in knowledge exchange, as well as their everyday experiences with working in multisectoral remits.

Methods

In 2015, we conducted participant observation during an interactive event with 41 stakeholders from national and local government, the third sector and academia in Cambridge, UK. Formal and informal interactions between stakeholders were recorded in observational field notes. We also conducted 18 semistructured interviews reflecting on the event and on knowledge exchange in general.

Results

We found that stakeholders negotiated a variety of challenges. First, stakeholders had to negotiate relatively new formal and informal multisectoral remits; and how to reconcile the differing expectations of transport specialists, who tended to emphasise the importance of precedence in guiding action, and health specialists’ concern for the rigour and synthesis of research evidence. Second, research in this field involved complex study designs, and often produced evidence with uncertain transferability to other settings. Third, health outcomes of transport schemes had political traction and were used strategically but not easily translated into cost-benefit ratios. Finally, knowledge exchange meant multiple directions of influence. Stakeholders were concerned that researchers did not always have skills to translate their findings into understandable evidence, and some stakeholders would welcome opportunities to influence research agendas.

Conclusions

This case study of stakeholders’ experiences indicates that multisectoral research, practice and policymaking requires the ability and capacity to locate, understand and communicate complex evidence from a variety of disciplines, and integrate different types of evidence into clear business cases beyond sectoral boundaries.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3940-x) contains supplementary material, which is available to authorized users.

Longitudinal associations of active commuting with body mass index

OBJECTIVE

To investigate the longitudinal associations between active commuting (walking and cycling to work) and body mass index (BMI).

METHOD

We used self-reported data on height, weight and active commuting from the Commuting and Health in Cambridge study (2009 to 2012; n=809). We used linear regression to test the associations between: a) maintenance of active commuting over one year and BMI at the end of that year; and b) change in weekly time spent in active commuting and change in BMI over one year.

RESULTS

After adjusting for sociodemographic variables, other physical activity, physical wellbeing and maintenance of walking, those who maintained cycle commuting reported a lower BMI on average at one year follow-up (1.14kg/m(2), 95% CI: 0.30 to 1.98, n=579) than those who never cycled to work. No significant association remained after adjustment for baseline BMI. No significant associations were observed for maintenance of walking. An increase in walking was associated with a reduction in BMI (0.32kg/m(2), 95% CI: 0.03 to 0.62, n=651, after adjustment for co-variates and baseline BMI) only when restricting the analysis to those who did not move. No other significant associations between changes in weekly time spent walking or cycling on the commute and changes in BMI were observed.

CONCLUSIONS

This work provides further evidence of the contribution of active commuting, particularly cycling, to preventing weight gain or facilitating weight loss. The findings may be valuable for employees choosing how to commute and engaging employers in the promotion of active travel.

Population Approaches to Prevention of Type 2 Diabetes

Martin White argues that whole population interventions will be needed in addition to those targeted to people at high risk in order to respond to the global challenge of type 2 diabetes.

Changing the environment to improve population health: a framework for considering exposure in natural experimental studies

There is renewed optimism regarding the use of natural experimental studies to generate evidence as to the effectiveness of population health interventions. Natural experimental studies capitalise on environmental and policy events that alter exposure to certain social, economic or environmental factors that influence health. Natural experimental studies can be useful for examining the impact of changes to ‘upstream’ determinants, which may not be amenable to controlled experiments. However, while natural experiments provide opportunities to generate evidence, they often present certain conceptual and methodological obstacles. Population health interventions that alter the physical or social environment are usually administered broadly across populations and communities. The breadth of these interventions means that variation in exposure, uptake and impact may be complex. Yet many evaluations of natural experiments focus narrowly on identifying suitable ‘exposed’ and ‘unexposed’ populations for comparison. In this paper, we discuss conceptual and analytical issues relating to defining and measuring exposure to interventions in this context, including how recent advances in technology may enable researchers to better understand the nature of population exposure to changes in the built environment. We argue that when it is unclear whether populations are exposed to an intervention, it may be advantageous to supplement traditional impact assessments with observational approaches that investigate differing levels of exposure. We suggest that an improved understanding of changes in exposure will assist the investigation of the impact of complex natural experiments in population health.