Yvonne L Michael

Drexel University, Philadelphia, Pennsylvania, United States

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Publications (89)237.51 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Evaluate associations of neighborhood social capital and mobility of older adults. A community-based survey (Philadelphia, 2010) assessed mobility (Life-Space Assessment [LSA]; range = 0-104) of older adults (n = 675, census tracts = 256). Social capital was assessed for all adults interviewed from 2002-2010 (n = 13,822, census tracts = 374). Generalized estimating equations adjusted for individual- and neighborhood-level characteristics estimated mean differences and 95% confidence intervals (CIs) in mobility by social capital tertiles. Interactions by self-rated health, living arrangement, and race were tested. Social capital was not associated with mobility after adjustment for other neighborhood characteristics (mean difference for highest versus lowest tertile social capital = 0.79, 95% CI = [-3.3, 4.8]). We observed no significant interactions. In models stratified by race, Black participants had higher mobility in high social capital neighborhoods (mean difference = 7.4, CI = [1.0, 13.7]). Social capital may not contribute as much as other neighborhood characteristics to mobility. Interactions between neighborhood and individual-level characteristics should be considered in research on mobility. © The Author(s) 2014.
  • Yvonne L Michael, Irene H Yen
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    ABSTRACT: Informal caregiving is common for older women and can negatively affect health, but its impact on physical function remains unclear. Using inverse probability weighting methods, we quantified the association of caregiving with physical function over 6 years.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 07/2014; DOI:10.1093/gerona/glu104 · 4.98 Impact Factor
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    ABSTRACT: ABSTRACT Background: The purpose of this study was to describe the longitudinal trajectories and bidirectional relationships of the physical-social and emotional functioning (EF) dimensions of positive aging and to identify their baseline characteristics. Methods: Women age 65 and older who enrolled in one or more Women's Health Initiative clinical trials (WHI CTs) and who had positive aging indicators measured at baseline and years 1, 3, 6, and 9 were included in these analyses (N = 2281). Analytic strategies included latent class growth modeling to identify longitudinal trajectories and multinomial logistic regression to examine the effects of baseline predictors on these trajectories. Results: A five-trajectory model was chosen to best represent the data. For Physical-Social Functioning (PSF), trajectory groups included Low Maintainer (8.3%), Mid-Low Improver (10.4%), Medium Decliner (10.7%), Mid-High Maintainer (31.2%), and High Maintainer (39.4%); for EF, trajectories included Low Maintainer (3%), Mid-Low Improver (9%), Medium Decliner (7.7%), Mid-High Maintainer (22.8%), and High Maintainer (57.5%). Cross-classification of the groups of trajectories demonstrated that the impact of a high and stable EF on PSF might be greater than the reverse. Low depression symptoms, low pain, and high social support were the most consistent predictors of high EF trajectories. Conclusion: Aging women are heterogeneous in terms of positive aging indicators for up to 9 years of follow-up. Interventions aimed at promoting sustainable EF might have diffused effects on other domains of healthy aging.
    International Psychogeriatrics 04/2014; 26(8):1-12. DOI:10.1017/S1041610214000593 · 1.89 Impact Factor
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    ABSTRACT: This study aims to determine whether vitamin D levels are associated with menopause-related symptoms in older women. A randomly selected subset of 1,407 women, among 26,104 potentially eligible participants of the Women's Health Initiative Calcium and Vitamin D trial of postmenopausal women aged 51 to 80 years, had 25-hydroxyvitamin D [25(OH)D] levels measured at the Women's Health Initiative Calcium and Vitamin D trial baseline visit. Information about menopause-related symptoms at baseline was obtained by questionnaire and included overall number of symptoms and composite measures of sleep disturbance, emotional well-being, and energy/fatigue, as well as individual symptoms. After exclusions for missing data, 530 women (mean [SD] age, 66.2 [6.8] y) were included in these analyses. Borderline significant associations between 25(OH)D levels and total number of menopausal symptoms were observed (with P values ranging from 0.05 to 0.06 for fully adjusted models); however, the effect was clinically insignificant and disappeared with correction for multiple testing. No associations between 25(OH)D levels and composite measures of sleep disturbance, emotional well-being, or energy/fatigue were observed (P's > 0.10 for fully adjusted models). There is no evidence for a clinically important association between serum 25(OH)D levels and menopause-related symptoms in postmenopausal women.
    Menopause (New York, N.Y.) 04/2014; DOI:10.1097/GME.0000000000000238 · 3.08 Impact Factor
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    ABSTRACT: Epidemiologists typically collect narrative descriptions of occupational histories because these are less prone than self-reported exposures to recall bias of exposure to a specific hazard. However, the task of coding these narratives can be daunting and prohibitively time-consuming in some settings. The aim of this manuscript is to evaluate the performance of a computer algorithm to translate the narrative description of occupational codes into standard classification of jobs (2010 Standard Occupational Classification) in an epidemiological context. The fundamental question we address is whether exposure assignment resulting from manual (presumed gold standard) coding of the narratives is materially different from that arising from the application of automated coding. We pursued our work through three motivating examples: assessment of physical demands in Women's Health Initiative observational study, evaluation of predictors of exposure to coal tar pitch volatiles in the US Occupational Safety and Health Administration's (OSHA) Integrated Management Information System, and assessment of exposure to agents known to cause occupational asthma in a pregnancy cohort. In these diverse settings, we demonstrate that automated coding of occupations results in assignment of exposures that are in reasonable agreement with results that can be obtained through manual coding. The correlation between physical demand scores based on manual and automated job classification schemes was reasonable (r = 0.5). The agreement between predictive probability of exceeding the OSHA's permissible exposure level for polycyclic aromatic hydrocarbons, using coal tar pitch volatiles as a surrogate, based on manual and automated coding of jobs was modest (Kendall rank correlation = 0.29). In the case of binary assignment of exposure to asthmagens, we observed that fair to excellent agreement in classifications can be reached, depending on presence of ambiguity in assigned job classification (κ = 0.5-0.8). Thus, the success of automated coding appears to depend on the setting and type of exposure that is being assessed. Our overall recommendation is that automated translation of short narrative descriptions of jobs for exposure assessment is feasible in some settings and essential for large cohorts, especially if combined with manual coding to both assess reliability of coding and to further refine the coding algorithm.
    Annals of Occupational Hygiene 02/2014; 58(4). DOI:10.1093/annhyg/meu006 · 2.07 Impact Factor
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    ABSTRACT: Neighborhood environment is consistently associated with obesity; changes to modifiable aspects of the neighborhood environment may curb the growth of obesity in the US and other developed nations. However, currently the majority of studies are cross-sectional and thus not appropriate for evaluating causality. The goal of this study was to evaluate the effect of a neighborhood-changing intervention on changes in obesity among older women. Over the past 30 years the Portland, Oregon metropolitan region has made significant investments in plans, regulatory structures, and public facilities to reduce sprawl and increase compact growth centers, transit-oriented development approaches, and green space. We used geocoded residential addresses to link data on land-use mix, public transit access, street connectivity, and access to green space from four time points between 1986 and 2004, with longitudinal data on body mass index (BMI) from a cohort of 2003 community-dwelling women aged 66 years and older. Height and weight were measured at clinic visits. Women self-reported demographics, health habits, and chronic conditions, and self-rated their health. Neighborhood socioeconomic status was assessed from census data. Neighborhood walkability and access to green space improved over the 18-year study period. On average there was a non-significant mean weight loss in the cohort between baseline (mean age 72.6 years) and the study's end (mean age 85.0 years). We observed no association between neighborhood built environment or change in built environment and BMI. Greater neighborhood socioeconomic status at baseline was independently associated with a healthier BMI at baseline, and protected against an age-related decline in BMI over time. BMI decreases with age reflect increased frailty, especially among older adults with complex morbidities. Future research should consider the influence of the neighborhood environment on additional relevant health outcomes and should include measures of the social environment in conjunction with built environment measures.
    Social Science [?] Medicine 02/2014; 102:129-37. DOI:10.1016/j.socscimed.2013.11.047 · 2.56 Impact Factor
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    ABSTRACT: Background Whether or not they allow smoking in their own homes, residents of multi-unit housing are exposed to significant second hand smoke (SHS). Exposure may be greater for families living in public housing, due to higher rates of tobacco use in these communities. Since 2009, HUD has supported local public housing authorities to enact policies to reduce SHS exposure, and many PHAs are working to develop and implement smoke-free policies. In Philadelphia, formative work was conducted in partnership with the Philadelphia Housing Authority (PHA) and the Philadelphia Department of Public Health, to better understand stakeholder readiness for smoke-free public housing. Methods During 2012, we conducted in-depth interviews (n=6) with PHA staff, resident leaders and other tobacco control stakeholders and focus groups (n=2) with public housing residents, both smokers and non-smokers. Data were transcribed and analyzed to identify themes related to current tobacco use in public housing communities, and stakeholder views on barriers and facilitators of smoke-free policy implementation. Results Current tobacco use in communities was perceived to be significant. Smoking and non-smoking residents were aware of SHS-related health risks, but less knowledgeable about the properties of SHS. Many used inadequate strategies for controlling SHS in homes (i.e., odor-reducing fragrances, having non-smoking rooms), or common areas (extinguishing cigarettes when children enter elevators) Smokers described motivation to quit. All residents welcomed health education and community forums on policy development. Staff concerns focused on resident attitudes, and resources for enforcement. Overall, stakeholders agreed that ideal processes for implementation relied on investments in resident education on SHS, cessation services tailored to resident needs, and collaborative policy development. Conclusions Implementation of smoke-free public housing policies requires cessation services, and considerable public health education, building on existing awareness of SHS-related health risks.
    141st APHA Annual Meeting and Exposition 2013; 11/2013
  • Amy E Leader, Yvonne L Michael
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    ABSTRACT: To examine the association between social capital and adherence to cancer screening exams. Data from a population-based survey assessed perceived neighborhood social capital as well as cancer screening behavior. We analyzed the influence of social capital on adherence to screening guidelines for cervical, breast, and colorectal cancer. Data from 2668 adults documented that those with greater perceived neighborhood social capital were more likely to be screened for cancer. The effect was strongest for colorectal cancer and weakest for cervical cancer. Research on understanding the effect of the neighborhood social environment on efforts related to cancer screening behavior may be helpful for increasing cancer screening rates.
    American journal of health behavior 09/2013; 37(5):683-92. DOI:10.5993/AJHB.37.5.12 · 1.31 Impact Factor
  • Nancy E. Findholt, Melinda M. Davis, Yvonne L. Michael
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    ABSTRACT: PurposeTo explore the perceived barriers, resources, and training needs of rural primary care providers in relation to implementing the American Medical Association Expert Committee recommendations for assessment, treatment, and prevention of childhood obesity.Methods In‐depth interviews were conducted with 13 rural primary care providers in Oregon. Transcribed interviews were thematically coded.ResultsBarriers to addressing childhood obesity fell into 5 categories: barriers related to the practice (time constraints, lack of reimbursement, few opportunities to detect obesity), the clinician (limited knowledge), the family/patient (family lifestyle and lack of parent motivation to change, low family income and lack of health insurance, sensitivity of the issue), the community (lack of pediatric subspecialists and multidisciplinary/tertiary care services, few community resources), and the broader sociocultural environment (sociocultural influences, high prevalence of childhood obesity). There were very few clinic and community resources to assist clinicians in addressing weight issues. Clinicians had received little previous training relevant to childhood obesity, and they expressed an interest in several topics.Conclusions Rural primary care providers face extensive barriers in relation to implementing recommended practices for assessment, treatment, and prevention of childhood obesity. Particularly problematic is the lack of local and regional resources. Employing nurses to provide case management and behavior counseling, group visits, and telehealth and other technological communications are strategies that could improve the management of childhood obesity in rural primary care settings.
    The Journal of Rural Health 08/2013; 29. DOI:10.1111/jrh.12006 · 1.77 Impact Factor
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    ABSTRACT: Diversity of neighborhood amenities may promote the mobility of older adults. A 2010 community-based sample of 510 adults aged ≥65 years in Philadelphia, Pennsylvania, and geospatial data from the Esri Business Analyst database (Esri, Inc., Redlands, California) were used to assess associations of neighborhood amenity diversity with mobility. Neighborhoods were defined by census tract, and diversity of amenities was derived by using the Leadership in Energy and Environmental Design's neighborhood development index (US Green Building Council, Washington, DC). Generalized estimating equations adjusted for demographic, socioeconomic, and neighborhood characteristics were used to estimate differences in mobility score by tertile of amenity diversity. Analyses were stratified by participants' routine travel habits (stayed at home, stayed in home zip code, or traveled beyond home zip code). We found that for those who spent most of their time in their home neighborhoods, mobility scores (from the Life-Space Assessment, which ranges from 0 to 104 points) were 8.3 points higher (95% confidence interval: 0.1, 16.6) among those who lived in neighborhoods with the most amenity diversity compared with those who lived in neighborhoods with the least amenity diversity. No significant associations between amenity diversity and mobility were observed for those who did not leave home or who regularly traveled outside their neighborhoods. Neighborhoods with a high diversity of amenities may be important promoters of mobility in older adults who do not routinely travel outside their neighborhoods.
    American journal of epidemiology 05/2013; 178(5). DOI:10.1093/aje/kwt032 · 4.98 Impact Factor
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    ABSTRACT: OBJECTIVE: To examine cross sectional associations between mobility with or without disability and social engagement in a community-based sample of older adults. METHODS: Social engagement of participants (n = 676) was outside the home (participation in organizations and use of senior centers) and in home (talking by phone and use of Internet). Logistic or proportional odds models evaluated the association between social engagement and position in the disablement process (no mobility limitations, mobility limitations/no disability, and mobility limitations/disability). RESULTS: Low mobility was associated with lower level of social engagement of all forms (Odds ratio (OR) = 0.59, confidence intervals (CI): 0.41-0.85 for organizations; OR = 0.67, CI: 0.42-1.06 for senior center; OR = 0.47, CI: 0.32-0.70 for phone; OR = 0.38, CI: 0.23-0.65 for Internet). For social engagement outside the home, odds of engagement were further reduced for individuals with disability. DISCUSSION: Low mobility is associated with low social engagement even in the absence of disability; associations with disability differed by type of social engagement.
    Journal of Aging and Health 04/2013; 25(4). DOI:10.1177/0898264313482489 · 1.56 Impact Factor
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    ABSTRACT: OBJECTIVES: To determine how the number of geriatric syndromes is associated with incident disability in community-based populations of older adults. DESIGN: Longitudinal analysis from the Women's Health Initiative Observational Study (WHI-OS). SETTING: Community. PARTICIPANTS: Twenty-nine thousand five hundred forty-four women aged 65 and older enrolled in the WHI-OS and free of disability in activities of daily living (ADLs) at baseline. MEASUREMENTS: Geriatric syndromes (high depressive symptoms, dizziness, falls, hearing or visual impairment, osteoporosis, polypharmacy, syncope, sleep disturbance, and urinary incontinence) were self-reported at baseline and 3-year follow-up. Disability was defined as dependence in any ADL and was assessed at baseline and follow-up. Chronic diseases were measured according to a modified Charlson Index. RESULTS: Geriatric syndromes were common in this population of women; 76.3% had at least one syndrome at baseline. Greater number of geriatric syndromes at baseline was significantly associated with greater risk of incident ADL disability at follow-up (P ≤ .001). Adjusted risk ratios were 1.21 (95% confidence interval (CI) = 0.78-1.87) for a single syndrome and 6.64 (95% CI = 4.15-10.62) for five or more syndromes compared with no syndromes. These results were only slightly attenuated after adjustment for number of chronic diseases or pain. CONCLUSION: Geriatric syndromes are significantly associated with onset of disability in older women; this association is not simply a result of chronic disease or pain. A better understanding of how these conditions contribute to disablement is needed. Geriatric syndrome assessment should be considered along with chronic disease management in the prevention of disability in older women.
    Journal of the American Geriatrics Society 03/2013; 61(3). DOI:10.1111/jgs.12147 · 4.22 Impact Factor
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    ABSTRACT: PURPOSE: Higher physical activity (PA) has been associated with greater attenuation of body-fat gain and preservation of lean mass across the lifespan. These analyses aimed to determine relationships of change in PA to changes in fat and lean body mass in a longitudinal prospective study of postmenopausal women. METHODS: Among 11,491 women enrolled at three Women's Health Initiative (WHI) clinical centers were selected to undergo dual-energy x-ray absorptiometry (DXA), 8,352 had baseline body composition measurements, with at least one repeated measure at yr 1, 3, and 6. PA data were obtained by self-report at baseline, 3 and 6 yr of follow-up. Time-varying PA impact on change in lean and fat mass during the six-yr study period for age groups (50-59y, 60-69y, 70- 79y) was estimated using mixed effects linear regression. RESULTS: Baseline PA and body composition differed significantly among the three age groups. The association of change in fat mass from baseline and time-varying PA differed across the three age groups (p=0.0006). In women aged 50-59, gain in fat mass from baseline was attenuated with higher levels of physical activity. Women aged 70-79 lost fat mass at all PA levels. In contrast, change in lean mass from baseline and time-varying PA did not differ by age group (p=0.1935). CONCLUSIONS: The association between PA and change in fat mass varies by age group, with younger, but not older, women benefitting from higher levels of aerobic PA. Higher levels of aerobic activity are not associated with changes in lean mass, which tends to decrease in older women regardless of activity level. Greater attention to resistance training exercises may be needed to prevent lean mass loss as women age.
    Medicine and science in sports and exercise 02/2013; DOI:10.1249/MSS.0b013e31828af8bd · 4.48 Impact Factor
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    ABSTRACT: We examined the association between neighborhood walkability and changes in body mass index (BMI) and obesity during a 14-year follow-up among community-dwelling women 71 years of age on average (n=1008 representing 253 census tracts). Multilevel models predicted change in BMI or incidence of obesity controlling for age, marital status, number of incident comorbidities, self rated health, and death, over a follow-up of 14 years. Among non-sedentary older women, average BMI remained stable (β=0.007, p=0.291); risk of becoming obese increased 3% per year (odds ratio=1.03, 95% CI 1.01, 1.05). Walkability was not associated with BMI or risk of obesity. Future research should consider additional neighborhood characteristics relevant to older adults, such as proximity to retail, public transit, or parks.
    Health & Place 02/2013; 22C:7-10. DOI:10.1016/j.healthplace.2013.02.001 · 2.44 Impact Factor
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    ABSTRACT: BACKGROUND: Several recent studies have identified a relationship between the natural environment and improved health outcomes. However, for practical reasons, most have been observational, cross-sectional studies. PURPOSE: A natural experiment, which provides stronger evidence of causality, was used to test whether a major change to the natural environment-the loss of 100 million trees to the emerald ash borer, an invasive forest pest-has influenced mortality related to cardiovascular and lower-respiratory diseases. METHODS: Two fixed-effects regression models were used to estimate the relationship between emerald ash borer presence and county-level mortality from 1990 to 2007 in 15 U.S. states, while controlling for a wide range of demographic covariates. Data were collected from 1990 to 2007, and the analyses were conducted in 2011 and 2012. RESULTS: There was an increase in mortality related to cardiovascular and lower-respiratory-tract illness in counties infested with the emerald ash borer. The magnitude of this effect was greater as infestation progressed and in counties with above-average median household income. Across the 15 states in the study area, the borer was associated with an additional 6113 deaths related to illness of the lower respiratory system, and 15,080 cardiovascular-related deaths. CONCLUSIONS: Results suggest that loss of trees to the emerald ash borer increased mortality related to cardiovascular and lower-respiratory-tract illness. This finding adds to the growing evidence that the natural environment provides major public health benefits.
    American journal of preventive medicine 02/2013; 44(2):139-145. DOI:10.1016/j.amepre.2012.09.066 · 4.24 Impact Factor
  • Progress in community health partnerships: research, education, and action 01/2013; 7(1):1-3. DOI:10.1353/cpr.2013.0004
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    ABSTRACT: The development of systematic and sustainable surveillance systems is necessary for the creation of patient safety prevention programs and the evaluation of improvement resulting from innovations. To that end, inpatient hospital discharges collected by the Pennsylvania Health Care Cost Containment Council were used to investigate patient safety events (PSEs) in Pennsylvania in 2006. PSEs were identified using external cause of injury codes (E-codes) in combination with the Agency for Healthcare Research and Quality's patient safety indicators (PSIs). Encounters with and without PSEs were compared with regard to patient age, sex, race, length of stay, and cost. Approximately 9% of all Pennsylvania inpatient discharges had a PSE in 2006. Patients with a PSE were on average older, male, and white. The average length of stay for a PSE was 3 days longer and $35 000 more expensive than a non-PSE encounter. It was concluded that E-codes and PSIs were useful tools for the surveillance of PSEs in Pennsylvania, and that administrative data from healthcare organizations provide a consistent source of standardized data related to patient encounters, creating an opportunity to describe PSEs at the population level.
    01/2013; 32(4):26-33. DOI:10.1002/jhrm.21107
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    ABSTRACT: Background: Chronic hepatitis B virus is a leading cause of primary liver cancer and cirrhosis, especially among Asian and Pacific Islander immigrants. Vaccination of high-risk groups is critical for controlling HBV. Objective: This study assessed the vaccination status and vaccine perceptions of high-risk APIs in Philadelphia. Methods: 935 participants were screened at 17 locations throughout Philadelphia. Participants completed a questionnaire regarding their country of birth, ethnicity, education, and perception of vaccination status. Participants were screened for infection and protection status. Infected individuals were referred to appropriate health care; vulnerable individuals were referred for vaccination. Fisher's exact test was performed to assess the difference between APIs and non-APIs with respect to their vaccine perception. Results: Overall, 6.4% (n = 60) were infected with HBV and 52.1% (n = 487) had protective antibodies. 6.5% (n = 56) of participants believed they were vaccinated, but had no protective antibodies. Of these participants, 87.5% (n = 49) were immigrants from high-risk countries; 67.9% (n = 38) were female; 39.3% (n = 22) had less than a college degree. There was no significant difference between APIs and non-APIs with respect to their vaccine perception (p > 0.05). Conclusions: It is critical that those at highest risk for HBV infection be protected via vaccination. This study indicates that some individuals have misconceptions regarding their vaccination status and self-report of HBV vaccine may be unreliable. This suggests the need for HBV education and screening, particularly among the immigrant population.
    140st APHA Annual Meeting and Exposition 2012; 10/2012
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    ABSTRACT: The objective was to investigate associations between features of the physical environment and neighborliness. Measures of the physical environment, including sidewalks, front porches, traffic-calming devices, bars on windows, and the presence of litter or graffiti, were collected using a systematic audit instrument in 10 neighborhoods in Portland, Oregon. Generalized linear regression models were created to model the odds of increasing neighborliness given access to the physical-environment factors of interest. The authors observed a greater probability of higher levels of neighborliness as the total number of positive physical-environment characteristics increased (cumulative odds ratio [95% confidence interval] = 1.69 [1.16, 2.45]) and the results were unchanged after controlling for race, self-reported health, perception of safety, years of neighborhood residence, age of house, market value of house, and proportion of homeowners in neighborhood. Modifiable features of the physical environment may be one mechanism through which people can enhance neighborliness.
    Environment and Behavior 09/2012; 44(5):595-615. DOI:10.1177/0013916511402058 · 1.27 Impact Factor

Publication Stats

1k Citations
237.51 Total Impact Points


  • 2009–2014
    • Drexel University
      • Department of Epidemiology and Biostatistics
      Philadelphia, Pennsylvania, United States
  • 2013
    • University of Pittsburgh
      • Department of Epidemiology
      Pittsburgh, Pennsylvania, United States
    • Thomas Jefferson University
      • Department of Medical Oncology
      Philadelphia, PA, United States
  • 2012
    • Portland State University
      • Institute of Portland Metropolitan Studies
      Portland, OR, United States
  • 2011–2012
    • University of Massachusetts Amherst
      • Division of Biostatistics and Epidemiology
      Amherst Center, MA, United States
    • Stanford University
      • Stanford Prevention Research Center
      Stanford, CA, United States
  • 2009–2012
    • Philadelphia University
      Filadelfia, Pennsylvania, United States
  • 2009–2010
    • Kaiser Permanente
      Oakland, California, United States
  • 2004–2009
    • Oregon Health and Science University
      • Department of Public Health & Preventive Medicine
      Portland, Oregon, United States