Using an agent-based model to simulate children’s active travel to school

Abstract Background Despite the multiple advantages of active travel to school, only a small percentage of US children and adolescents walk or bicycle to school. Intervention studies are in a relatively early stage and evidence of their effectiveness over long periods is limited. The purpose of this study was to illustrate the utility of agent-based models in exploring how various policies may influence children’s active travel to school. Methods An agent-based model was developed to simulate children’s school travel behavior within a hypothetical city. The model was used to explore the plausible implications of policies targeting two established barriers to active school travel: long distance to school and traffic safety. The percent of children who walk to school was compared for various scenarios. Results To maximize the percent of children who walk to school the school locations should be evenly distributed over space and children should be assigned to the closest school. In the case of interventions to improve traffic safety, targeting a smaller area around the school with greater intensity may be more effective than targeting a larger area with less intensity. Conclusions Despite the challenges they present, agent based models are a useful complement to other analytical strategies in studying the plausible impact of various policies on active travel to school.http://deepblue.lib.umich.edu/bitstream/2027.42/112566/1/12966_2012_Article_757.pd

Integrating social and biological factors in health research: a systems view

An important focus of recent calls for interdisciplinary approaches in health research has been the integration of social and biomedical sciences in understanding the causes of ill-health. Typical models for the incorporation of social factors into biomedical research include social factors as distal antecedents of more proximate biologic factors and gene-environment interaction. Under both models the distinction between social and biologic factors remains clear-cut, and consideration of social factors is not indispensable for understanding the biologic processes leading to disease. However, recent evidence suggests that social and biologic processes are inextricably linked in systems. This paper reviews models for the incorporation of social factors into the study of health, discusses the potentialities of systems approaches, and highlights implications for population health and epidemiologyhttp://deepblue.lib.umich.edu/bitstream/2027.42/57779/1/Integrating Social and Biological Factors in Health Research A systems view.pd

The persistent puzzle of the geographic patterning of cardiovascular disease

Not Availablehttp://deepblue.lib.umich.edu/bitstream/2027.42/78521/1/DiezRoux2009_PrevMed.pd

Commentary:Estimating and understanding area health effects

http://deepblue.lib.umich.edu/bitstream/2027.42/57894/1/Commentary Estimating and understanding area health effects.pd

A glossary for multilevel analysis

http://deepblue.lib.umich.edu/bitstream/2027.42/56188/1/Diez Roux AV, A Glossary of Multilevel Analysis, 2002.pd

The contextual effect of the local food environment on residents' diets: the atherosclerosis risk in communities study

OBJECTIVES: We studied the association between the local food environment and residents' report of recommended dietary intake. METHODS: Recommended intakes of foods and nutrients for 10 623 Atherosclerosis Risk in Communities participants were estimated from food frequency questionnaires. Supermarkets, grocery stores, and full-service and fast-food restaurants were geocoded to census tracts. RESULTS: Black Americans' fruit and vegetable intake increased by 32% for each additional supermarket in the census tract (relative risk [RR] = 1.32; 95% confidence interval [CI] = 1.08, 1.60). White Americans' fruit and vegetable intake increased by 11% with the presence of 1 or more supermarket (RR = 1.11; 95% CI = 0.93, 1.32). CONCLUSIONS: These findings suggest the local food environment is associated with residents' recommended diets.http://deepblue.lib.umich.edu/bitstream/2027.42/57740/1/The Contextual Effect of the local food environment on residents diets.pd

Left ventricular mass and ventricular remodeling among Hispanic subgroups compared with non-Hispanic blacks and whites: MESA (Multi-ethnic Study of Atherosclerosis).

OBJECTIVES: The purpose of this study was to examine the prevalence of left ventricular hypertrophy (LVH) and left ventricular (LV) remodeling patterns within Hispanic subgroups compared with non-Hispanic whites in the MESA (Multi-Ethnic Study of Atherosclerosis). BACKGROUND: Hispanics are the largest and fastest-growing ethnic minority in the U.S., but there are no data on LVH and LV geometry among Hispanic subgroups. METHODS: Cardiac magnetic resonance imaging was performed in 4,309 men and women age 45 to 84 years without clinical cardiovascular disease. Hispanics were categorized into subgroups based on self-reported ancestry. LVH was defined as the upper 95th percentile of indexed LV mass in a reference normotensive, nondiabetic, nonobese population, and LV remodeling according to the presence/absence of LVH and abnormal/normal LV mass to LV end-diastolic volume ratio. RESULTS: Among Hispanic participants, 574 were of Mexican origin, 329 were of Caribbean origin, and 161 were of Central/South American origin. On unadjusted analysis, only Caribbean-origin Hispanics (prevalence ratio = 1.2; 95% confidence interval [CI]: 1.03 to 1.4) had greater prevalence of hypertension than non-Hispanic whites. Hispanic subgroups were more likely to have LVH than non-Hispanic whites after adjustment for hypertension and other covariates (Caribbean-origin Hispanics = odds ratio [OR]: 1.8, 95% CI: 1.1 to 3.0; Mexican-origin Hispanics = OR: 2.2, 95% CI: 1.4 to 3.3; Central/South Americans = OR: 1.5, 95% CI: 0.7 to 3.1). All Hispanic subgroups also had a higher prevalence of concentric and eccentric hypertrophy compared with non-Hispanic whites (p < 0.001). CONCLUSIONS: Caribbean-origin Hispanics had a higher prevalence of LVH and abnormal LV remodeling compared with non-Hispanic whites. A higher prevalence of LVH and abnormal LV remodeling was also observed among Mexican-origin Hispanics, despite a lower prevalence of hypertension. Differences among Hispanic subgroups regarding LVH and LV remodeling should be taken into account when evaluating cardiovascular risk in this population.http://deepblue.lib.umich.edu/bitstream/2027.42/78513/1/RodriguezDiezRoux2010_J Am Coll Cardiol.pd

Estimating the neighborhood health effects: The challenges of casual inference in a complex world

http://deepblue.lib.umich.edu/bitstream/2027.42/57893/1/Estimating neighborhood health effects The challenges of casual inference in a complex world.pd

Investigating neighborhood and area effects on health.

The past few years have witnessed an explosion of interest in neighborhood or area effects on health. Several types of empiric studies have been used to examine possible area or neighborhood effects, including ecologic studies relating area characteristics to morbidity and mortality rates, contextual and multilevel analyses relating area socioeconomic context to health outcomes, and studies comparing small numbers of well-defined neighborhoods. Strengthening inferences regarding the presence and magnitude of neighborhood effects will require addressing a series of conceptual and methodological issues. Many of these issues relate to the need to develop theory and specific hypotheses on the processes through which neighborhood and individual factors may jointly influence specific health outcomes. Important challenges include defining neighborhoods or relevant geographic areas, identifying significant area or neighborhood characteristics, specifying the role of individual-level variables, incorporating life-course and longitudinal dimensions, combining a variety of research designs, and avoiding reductionism in the way in which "neighborhood" factors are incorporated into models of disease causation and quantitative analyses.analyses.http://deepblue.lib.umich.edu/bitstream/2027.42/78995/1/DiezRoux2001_AJPH.pd