Ellen K. Cromley

The Built Environment and Location-Based Physical Activity

BACKGROUND Studies of the built environment and physical activity have implicitly assumed that a substantial amount of activity occurs near home, but in fact the location is unknown. PURPOSE This study aims to examine associations between built environment variables within home and work buffers and moderate-to-vigorous physical activity (MVPA) occurring within these locations. METHODS Adults (n=148) from Massachusetts wore an accelerometer and GPS unit for up to 4 days. Levels of MVPA were quantified within 50-m and 1-km home and work buffers. Multiple regression models were used to examine associations between five objective built environment variables within 1-km home and work buffers (intersection density, land use mix, population and housing unit density, vegetation index) and MVPA within those areas. RESULTS The mean daily minutes of MVPA accumulated in all locations=61.1+/-32.8, whereas duration within the 1-km home buffers=14.0+/-16.4 minutes. Intersection density, land use mix, and population and housing unit density within 1-km home buffers were positively associated with MVPA in the buffer, whereas a vegetation index showed an inverse relationship (all p<0.05). None of these variables showed associations with total MVPA. Within 1 km of work, only population and housing unit density were significantly associated with MVPA within the buffer. CONCLUSIONS Findings are consistent with studies showing that certain attributes of the built environment around homes are positively related to physical activity, but in this case only when the outcome was location-based. Simultaneous accelerometer-GPS monitoring shows promise as a method to improve understanding of how the built environment influences physical activity behaviors by allowing activity to be quantified in a range of physical contexts and thereby provide a more explicit link between physical activity outcomes and built environment exposures.

The Effect of Tobacco Outlet Density and Proximity on Smoking Cessation

OBJECTIVES We examined the influence of tobacco outlet density and residential proximity to tobacco outlets on continuous smoking abstinence 6 months after a quit attempt. METHODS We used continuation ratio logit models to examine the relationships of tobacco outlet density and tobacco outlet proximity with biochemically verified continuous abstinence across weeks 1, 2, 4, and 26 after quitting among 414 adult smokers from Houston, Texas (33% non-Latino White, 34% non-Latino Black, and 33% Latino). Analyses controlled for age, race/ethnicity, partner status, education, gender, employment status, prequit smoking rate, and the number of years smoked. RESULTS Residential proximity to tobacco outlets, but not tobacco outlet density, provided unique information in the prediction of long-term, continuous abstinence from smoking during a specific quit attempt. Participants residing less than 250 meters (P = .01) or less than 500 meters (P = .04) from the closest tobacco outlet were less likely to be abstinent than were those living 250 meters or farther or 500 meters or farther, respectively, from outlets. CONCLUSIONS Because residential proximity to tobacco outlets influences smoking cessation, zoning restrictions to limit tobacco sales in residential areas may complement existing efforts to reduce tobacco use.

Density and proximity of fast food restaurants and body mass index among African Americans.

OBJECTIVES The purpose of this study was to address current gaps in the literature by examining the associations of fast food restaurant (FFR) density around the home and FFR proximity to the home, respectively, with body mass index (BMI) among a large sample of African American adults from Houston, Texas. METHODS We used generalized linear models with generalized estimating equations to examine associations of FFR density at 0.5-, 1-, 2-, and 5-mile road network buffers around the home with BMI and associations of the closest FFR to the home with BMI. All models were adjusted for a range of individual-level covariates and neighborhood socioeconomic status. We additionally investigated the moderating effects of household income on these relations. Data were collected from December 2008 to July 2009. RESULTS FFR density was not associated with BMI in the main analyses. However, FFR density at 0.5, 1, and 2 miles was positively associated with BMI among participants with lower incomes (P ≤ .025). Closer FFR proximity was associated with higher BMI among all participants (P < .001), with stronger associations emerging among those of lower income (P < .013) relative to higher income (P < .014). CONCLUSIONS Additional research with more diverse African American samples is needed, but results supported the potential for the fast food environment to affect BMI among African Americans, particularly among those of lower economic means.

Virtual and actual: Relative accuracy of on-site and web-based instruments in auditing the environment for physical activity

OBJECTIVES To assess the relative accuracy and usefulness of web tools in evaluating and measuring street-scale built environment characteristics. METHODS A well-known audit tool was used to evaluate 84 street segments at the urban edge of metropolitan Boston, Massachusetts, using on-site visits and three web-based tools. The assessments were compared to evaluate their relative accuracy and usefulness. RESULTS Web-based audits, based-on Google Maps, Google Street View, and MS Visual Oblique, tend to strongly agree with on-site audits on land-use and transportation characteristics (e.g., types of buildings, commercial destinations, and streets). However, the two approaches to conducting audits (web versus on-site) tend to agree only weakly on fine-grain, temporal, and qualitative environmental elements. Among the web tools used, auditors rated MS Visual Oblique as the most valuable. Yet Street View tends to be rated as the most useful in measuring fine-grain features, such as levelness and condition of sidewalks. CONCLUSION While web-based tools do not offer a perfect substitute for on-site audits, they allow for preliminary audits to be performed accurately from remote locations, potentially saving time and cost and increasing the effectiveness of subsequent on-site visits.

Subject loss in spatial analysis of breast cancer

Possible selection bias from assignment of latitude-longitude coordinates to the place of residence of all Connecticut women diagnosed with breast cancer from 1992 to 1995 (N = 11,470) was evaluated. Exact address-matching was accomplished for 8,121 records (70.8%) and an additional 1,722 records (15.0%) were matched using relaxed criteria. We did not address-match 1,627 records (14.1%) due to missing address information or limitations of the Geographic Information Systems street file. The age-adjusted likelihood of address-matching records was significantly greater for women of color, those born within Connecticut, residents of urban locales or census tracts with low median family incomes and those cases diagnosed nearer to 1992. Few differences in address-matching were attributable to tumor characteristics or therapeutic modality.

Choropleth map legend design for visualizing community health disparities

BackgroundDisparities in health outcomes across communities are a central concern in public health and epidemiology. Health disparities research often links differences in health outcomes to other social factors like income. Choropleth maps of health outcome rates show the geographical distribution of health outcomes. This paper illustrates the use of cumulative frequency map legends for visualizing how the health events are distributed in relation to social characteristics of community populations. The approach uses two graphs in the cumulative frequency legend to highlight the difference between the raw count of the health events and the raw count of the social characteristic like low income in the geographical areas of the map. The approach is applied to mapping publicly available data on low birth weight by town in Connecticut and Lyme disease incidence by town in Connecticut in relation to income. The steps involved in creating these legends are described in detail so that health analysts can adopt this approach.ResultsThe different health problems, low birth weight and Lyme disease, have different cumulative frequency signatures. Graphing poverty population on the cumulative frequency legends revealed that the poverty population is distributed differently with respect to the two different health problems mapped here.ConclusionCumulative frequency legends can be useful supplements for choropleth maps. These legends can be constructed using readily available software. They contain all of the information found in standard choropleth map legends, and they can be used with any choropleth map classification scheme. Cumulative frequency legends effectively communicate the proportion of areas, the proportion of health events, and/or the proportion of the denominator population in which the health events occurred that falls within each class interval. They illuminate the context of disease through graphing associations with other variables.

Demographic predictors of asthma treatment site: outpatient, inpatient, or emergency department.

OBJECTIVE To identify the demographic predictors of asthma treatment site: outpatient clinic, emergency department, or hospital. METHODS From the November 1993 to July 1995 claims data of the University of Connecticut Health Center, asthmatic patient sex, age, racial/ethnic group, address, and health insurance status were examined to identify predictors of treatment site. Patient addresses generated maps and census data. RESULTS 3288 visits were made by 1455 patients; 8%, 34%, and 58% came from poverty level, low, and higher income residential areas, respectively. Insurance type and then age were the most significant predictors of treatment site. Adults having commercial insurance or Medicare were most likely treated as outpatients, self-pay patients 5 times more likely in the emergency department, and those receiving public assistance 2.4 times more likely in the hospital. Only 9% of Medicaid children and 22% with commercial insurance were evaluated as outpatients. Neither sex nor race/ethnicity was an important predictor of treatment site. CONCLUSION Although not population-based, this group of asthmatic patients represents a group diverse in socioeconomic status and racial/ethnic background. Insurance category was the most influential factor predicting asthma treatment site, suggesting that economic status may be the most important determinant of higher morbidity. Children were treated predominantly in acute care settings.

Relationships Between the Built Environment and Walking and Weight Status Among Older Women in Three U.S. States

There are few studies of built environment associations with physical activity and weight status among older women in large geographic areas that use individual residential buffers to define environmental exposures. Among 23,434 women (70.0 ± 6.9 yr; range = 57-85) in 3 states, relationships between objective built environment variables and meeting physical activity recommendations via walking and weight status were examined. Differences in associations by population density and state were explored in stratified models. Population density (odds ratio [OR] =1.04 [1.02, 1.07]), intersection density (ORs = 1.18-1.28), and facility density (ORs = 1.01-1.53) were positively associated with walking. Density of physical activity facilities was inversely associated with overweight/obesity (OR = 0.69 [0.49, 0.96]). The strongest associations between facility density variables and both outcomes were found among women from higher population density areas. There was no clear pattern of differences in associations across states. Among older women, relationships between accessible facilities and walking may be most important in more densely populated settings.

Availability, accessibility and promotion of smokeless tobacco in a low-income area of Mumbai

Objective To examine the role of accessibility, product availability, promotions and social norms promotion, factors contributing to the use of smokeless tobacco (ST) products in a typical low-income community of Mumbai community using Geographic Information System (GIS), observational and interview methodologies and to assess implementation of Cigatettes and other Tobacco Products Act (COTPA) legislation. Rationale In India, the third largest producer of tobacco in the world, smokeless tobacco products are used by men, women and children. New forms of highly addictive packaged smokeless tobacco products such as gutkha are inexpensive and rates of use are higher in low-income urban communities. These products are known to increase rates of oral cancer and to affect reproductive health and fetal development. Methods The study used a mixed methods approach combining ethnographic and GIS mapping, observation and key informant interviews. Accessibility was defined as density, clustering and distance of residents and schools to tobacco outlets. Observation and interview data with shop owners and community residents produced an archive of products, information on shop histories and income and normative statements. Results Spatial analysis showed high density of outlets with variations across subcommunities. All residents can reach tobacco outlets within 30–100 feet of their homes. Normative statements from 55 respondents indicate acceptance of mens, womens and childrens use, and selling smokeless tobacco is reported to be an important form of income generation for some households. Multilevel tobacco control and prevention strategies including tobacco education, community norms change, licensing and surveillance and alternative income generation strategies are needed to reduce accessibility and availability of smokeless tobacco use.

Evaluation of the Placement of Mobile Fruit and Vegetable Vendors to Alleviate Food Deserts in New York City

Introduction In 2008, the New York City (NYC) health department licensed special mobile produce vendors (Green Carts) to increase access to fruits and vegetables in neighborhoods with the lowest reported fruit and vegetable consumption and the highest obesity rates. Because economic incentives may push vendors to locate in more trafficked, less produce-deprived areas, we examined characteristics of areas with and without Green Carts to explore whether Carts are positioned to reach the intended populations. Methods Using ArcGIS software, we mapped known NYC Green Cart locations noted through 2013 and generated a list of potential (candidate) sites where Carts could have located. We compared the food environment (via categorizing “healthy” or “unhealthy” food stores using federal classification codes corroborated by online storefront images) and other factors that might explain Cart location (eg, demographic, business, neighborhood characteristics) near actual and candidate sites descriptively and inferentially. Results Seven percent of Green Carts (n = 265) were in food deserts (no healthy stores within one-quarter mile) compared with 36% of candidate sites (n = 644, P < .001). Most Carts (78%) were near 2 or more healthy stores. Green Carts had nearly 60 times the odds of locating near subway stops (P < .001), were closer to large employers (odds ratio [OR], 6.4; P < .001), other food stores (OR, 14.1; P < .001), and in more populous tracts (OR, 2.9, P <.01) compared with candidate sites. Conclusion Green Carts were rarely in food deserts and usually had multiple healthy stores nearby, suggesting that Carts may not be serving the neediest neighborhoods. Exploration of Carts’ benefits in non–food desert areas is needed, but incentivizing vendors to locate in still-deprived places may increase program impact.