Access to mammography screening in a large urban population: a multi-level analysis

The role of mesolevel characteristics of the health care system and socioeconomic factors on health care use - results of a scoping review

BACKGROUND

Besides macrolevel characteristics of a health care system, mesolevel access characteristics can exert influence on socioeconomic inequalities in healthcare use. These reflect access to healthcare, which is shaped on a smaller scale than the national level, by the institutions and establishments of a health system that individuals interact with on a regular basis. This scoping review maps the existing evidence about the influence of mesolevel access characteristics and socioeconomic position on healthcare use. Furthermore, it summarizes the evidence on the interaction between mesolevel access characteristics and socioeconomic inequalities in healthcare use.

METHODS

We used the databases MEDLINE (PubMed), Web of Science, Scopus, and PsycINFO and followed the 'Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols extension for scoping reviews (PRISMA-ScR)' recommendations. The included quantitative studies used a measure of socioeconomic position, a mesolevel access characteristic, and a measure of individual healthcare utilisation. Studies published between 2000 and 2020 in high income countries were considered.

RESULTS

Of the 9501 potentially eligible manuscripts, 158 studies were included after a two-stage screening process. The included studies contained a wide spectrum of outcomes and were thus summarised to the overarching categories: use of preventive services, use of curative services, and potentially avoidable service use. Exemplary outcomes were screening uptake, physician visits and avoidable hospitalisations. Access variables included healthcare system characteristics such as physician density or distance to physician. The effects of socioeconomic position on healthcare use as well as of mesolevel access characteristics were investigated by most studies. The results show that socioeconomic and access factors play a crucial role in healthcare use. However, the interaction between socioeconomic position and mesolevel access characteristics is addressed in only few studies.

CONCLUSIONS

Socioeconomic position and mesolevel access characteristics are important when examining variation in healthcare use. Additionally, studies provide initial evidence that moderation effects exist between the two factors, although research on this topic is sparse. Further research is needed to investigate whether adapting access characteristics at the mesolevel can reduce socioeconomic inequity in health care use.

The role of language in mammography orders among low-income Latinas over a 10-year period

INTRODUCTION

Latinas in the United States have higher mortality from breast cancer, but longitudinal studies of mammography ordering (a crucial initial step towards screening) in primary care are lacking.

METHODS

We conducted an analysis of mammography order rates in Latinas (by language preference) and non-Latina white women (N = 181,755) over a > 10 year period in a multi-state network of community health centers (CHCs). We evaluated two outcomes (ever having a mammogram order and annual rate of mammography orders) using generalized estimating equation modeling.

RESULTS

Approximately one-third of all patients had ever had a mammogram order. Among those receiving mammogram orders, English-preferring Latinas had lower mammogram order rates than non-Hispanic white women (RR = 0.92, 95% CI = 0.89-0.95). Spanish-preferring Latinas had higher odds of ever having a mammogram ordered than non-Hispanic whites (odds ratio = 2.12, 95% CI = 2.06-2.18) and, if ever ordered, had a higher rate of annual mammogram orders (rate ratio = 1.53, 95% CI = 1.50-1.56).

CONCLUSION

These findings suggest that breast cancer detection barriers in low-income Latinas may not stem from a lack of orders in primary care, but in the subsequent accessibility of receiving ordered services.

Preventive care use among Hispanic adults with limited comfort speaking English: An analysis of the Medical Expenditure Panel Survey data

Language barriers have been associated with worse access to healthcare and poorer health outcomes. To assess differences in access to care and utilization of healthcare services between Hispanic adults and non-Hispanic white adults (NHW), we used the Medical Expenditure Panel Survey (2013-2016) to compare Hispanic adults who expressed limited comfort speaking in English (LCE) with Hispanic adults who were comfortable speaking in English (CE) and NHW adults. Hispanic adults with CE were less likely than NHW adults to have a usual source of care, use preventive services, including cervical cancer screening, and healthcare services. However, after adjustment breast and cervical cancer screening exceeded that of NHW adults. Hispanic adults with LCE fared substantially worse than their Hispanic counterparts with CE in having a usual source of care, use of preventive services, breast and colorectal cancer screening, and healthcare services. After adjustment, use of all cancer screening tests were similar. Eliminating disparities for Hispanic adults will require a multi-pronged approach to address access to healthcare and other social determinants of health, including poverty, employment discrimination, and educational inequities. The public health community can help improve health literacy, address barriers to care, and provide appropriate language assistance at point of care using culturally-competent means to promote greater utilization of preventive services, including demand for and delivery of cancer screenings.

Contextual factors associated with cancer screening uptake: A systematic review of observational studies

We conducted a systematic review of a wide range of contextual factors related to cancer screening uptake that have been studied so far. Studies were identified through PubMed and Web of Science databases. An operational definition of context was proposed, considering as contextual factors: social relations directly aimed at cancer screening, health care provider and facility characteristics, geographical/accessibility measures and aggregated measures at supra-individual level. We included 70 publications on breast, cervical and/or colorectal cancer screening from 42 countries, covering a data period of 24 years. A wide diversity of factors has been investigated in the literature so far. While several of them, as well as many interactions, were robustly associated with screening uptake (family, friends or provider recommendation, provider sex and experience, area-based socio-economic status…), others showed less consistency (ethnicity, urbanicity, travel time, healthcare density …). Screening inequities were not fully explained through adjustment for individual and contextual factors. Context, in its diversity, influences individual screening uptake and lots of contextual inequities in screening are commonly shared worldwide. However, there is a lack of frameworks, standards and definitions that are needed to better understand what context is, how it could modify individual behaviour and the ways of measuring and modifying it.

Geographic access to mammography facilities and frequency of mammography screening

PURPOSE

To assess the association between geographic access to mammography facilities and women's mammography utilization frequency.

METHODS

Using data from the population-based 1995-2007 Wisconsin Women's Health study, we used proportional odds and logistic regression to test whether driving times to mammography facilities and the number of mammography facilities within 10 km of women's homes were associated with mammography frequency among women aged 50-74 years and whether associations differed between Rural-Urban Commuting Areas and income and education groups.

RESULTS

We found evidence for nonlinear relationships between geographic access and mammography utilization (nonlinear effects of driving times and facility density, P-values .01 and .005, respectively). Having at least one nearby mammography facility was associated with greater mammography frequency among urban women (1 vs. 0 facilities, odds ratio 1.26, 95% confidence interval, 1.09-1.47), with similar effects among rural women. Adding more facilities had decreasing marginal effects. Long driving times tended to be associated with lower mammography frequency. We found no effect modification by income, education, or urbanicity. In rural settings, mammography nonuse was higher, facility density smaller, and driving times to facilities were longer.

CONCLUSIONS

Having at least one mammography facility near one's home may increase mammography utilization, with decreasing effects per each additional facility.

Risk Factors for Late Screening Mammography

BACKGROUND

Breast cancer has the highest incidence of cancers in women in the United States. Previous research has shown that screening mammography contributes to reduced breast cancer mortality. This study aimed to clarify why late screening might occur in an at-risk population.

MATERIALS AND METHODS

This study was a prospective cross-sectional study including 758 patients presenting to our radiology department for routine screening mammography who completed a 30-question survey regarding personal characteristics and mammography history. Univariate and multivariate logistic regression were performed to determine whether survey responses correlated with late screening.

RESULTS

Of the 758 patients, 184 (24%) were noncompliant with screening mammography guidelines. Risk factors for late screening included younger age (P = 0.001), white race/ethnicity (P = 0.03), self-reported lack of financial means or health insurance (P = 0.005), lack of satisfaction with a previous mammogram experience (P = 0.001), inadequate mammography education by a physician (P = 0.001), and lack of awareness/comprehension of screening mammography guidelines (P = 0.002).

CONCLUSION

Many factors contribute to late screening mammography. Although some are outside physician control, others can be influenced: patient education regarding screening mammography guidelines, and patient satisfaction with the mammography experience. This study highlights the importance of communication with and education of patients.

Contextual effects and cancer outcomes in the United States: a systematic review of characteristics in multilevel analyses

PURPOSE

There is increasing call for the utilization of multilevel modeling to explore the relationship between place-based contextual effects and cancer outcomes in the United States. To gain a better understanding of how contextual factors are being considered, we performed a systematic review.

METHODS

We reviewed studies published between January 1, 2002 and December 31, 2016 and assessed the following attributes: (1) contextual considerations such as geographic scale and contextual factors used; (2) methods used to quantify contextual factors; and (3) cancer type and outcomes. We searched PubMed, Scopus, and Web of Science and initially identified 1060 studies. One hundred twenty-two studies remained after exclusions.

RESULTS

Most studies utilized a two-level structure; census tracts were the most commonly used geographic scale. Socioeconomic factors, health care access, racial/ethnic factors, and rural-urban status were the most common contextual factors addressed in multilevel models. Breast and colorectal cancers were the most common cancer types, and screening and staging were the most common outcomes assessed in these studies.

CONCLUSIONS

Opportunities for future research include deriving contextual factors using more rigorous approaches, considering cross-classified structures and cross-level interactions, and using multilevel modeling to explore understudied cancers and outcomes.

Breast Cancer Screening for Patients of Rural Accountable Care Organization Clinics: A Multi-Level Analysis of Barriers and Facilitators

Not all women 50-74 years received biennial mammography and the situation is worse in rural areas. Accountable care organizations (ACO) emphasize coordinated care, use of electronic health system, and preventive quality measures and these practices may improve their patients' breast cancer screening rate. Using medical record data of 8,347 women patients aged 50-74 years from eight rural ACO clinics in Nebraska, this study examined patient-, provider-, and county-level barriers and facilitators for breast cancer screening. A generalized estimating equations model was used to account for the correlation among patients from the same provider and county. The multi-level logistic regression results suggest that uninsured non-Hispanic Black patients were less likely to meet the biennial mammography screening guideline. Patients whose preferred language being English, having a preventive visit in the past 12 months, having one or more chronic conditions were more likely to meet the biennial mammography screening guideline. Patients with a primary care provider (PCP) that was male, without a medical doctor degree were less likely to screen biennially. Patients with a PCP that reviewed performance report quarterly, or manually checked patients' mammography screening status during visits were more likely to screen biennially. Interestingly, patients whose PCP reported being reminded by a care coordination team were less likely to screen biennially. Patients living in counties with more PCPs were also more likely to screen biennially. The study findings suggest that efforts targeting individual and practice-level barriers could be most effective in improving mammography screening for these rural ACO patients.

Impact of geographic accessibility on utilization of the annual health check-ups by income level in Japan: A multilevel analysis

Although both geographic accessibility and socioeconomic status have been indicated as being important factors for the utilization of health care services, their combined effect has not been evaluated. The aim of this study was to reveal whether an income-dependent difference in the impact of geographic accessibility on the utilization of government-led annual health check-ups exists. Existing data collected and provided by Chiba City Hall were employed and analyzed as a retrospective cohort study. The subjects were 166,966 beneficiaries of National Health Insurance in Chiba City, Japan, aged 40 to 74 years. Of all subjects, 54,748 (32.8%) had an annual health check-up in fiscal year 2012. As an optimal index of geographic accessibility has not been established, five measures were calculated: travel time to the nearest health care facility, density of health care facilities (number facilities within a 30-min walking distance from the district of residence), and three indices based on the two-step floating catchment area method. Three-level logistic regression modeling with random intercepts for household and district of residence was performed. Of the five measures, density of health care facilities was the most compatible according to Akaike's information criterion. Both low density and low income were associated with decreased utilization of the health check-ups. Furthermore, a linear relationship was observed between the density of facilities and utilization of the health check-ups in all income groups and its slope was significantly steeper among subjects with an equivalent income of 0.00 yen than among those with equivalent income of 1.01-2.00 million yen (p = 0.028) or 2.01 million yen or more (p = 0.040). This result indicated that subjects with lower incomes were more susceptible to the effects of geographic accessibility than were those with higher incomes. Thus, better geographic accessibility could increase the health check-up utilization and also decrease the income-related disparity of utilization.

Are differences in travel time or distance to healthcare for adults in global north countries associated with an impact on health outcomes? A systematic review

OBJECTIVES

To investigate whether there is an association between differences in travel time/travel distance to healthcare services and patients' health outcomes and assimilate the methodologies used to measure this.

DESIGN

Systematic Review. We searched MEDLINE, Embase, Web of Science, Transport database, HMIC and EBM Reviews for studies up to 7 September 2016. Studies were excluded that included children (including maternity), emergency medical travel or countries classed as being in the global south.

SETTINGS

A wide range of settings within primary and secondary care (these were not restricted in the search).

RESULTS

108 studies met the inclusion criteria. The results were mixed. 77% of the included studies identified evidence of a distance decay association, whereby patients living further away from healthcare facilities they needed to attend had worse health outcomes (eg, survival rates, length of stay in hospital and non-attendance at follow-up) than those who lived closer. 6 of the studies identified the reverse (a distance bias effect) whereby patients living at a greater distance had better health outcomes. The remaining 19 studies found no relationship. There was a large variation in the data available to the studies on the patients' geographical locations and the healthcare facilities attended, and the methods used to calculate travel times and distances were not consistent across studies.

CONCLUSIONS

The review observed that a relationship between travelling further and having worse health outcomes cannot be ruled out and should be considered within the healthcare services location debate.

Contextual factors associated with uptake of breast and cervical cancer screening: A systematic review of the literature

Existing research on barriers to breast and cervical cancer screening uptake has focused primarily on socio-demographic characteristics of individuals. However, contextual factors, such as service organization, as well as healthcare providers' training and practices, are more feasibly altered to increase health service use. The objective of the authors in this study was to perform a critical systematic review of the literature to identify contextual factors at the provider- and system-level that were associated with breast and cervical cancer screening uptake. Studies published from 2000 to 2013 were identified through PubMed and PsycInfo. Methodologic quality was assessed, and studies were examined for themes related to provider- and system-level factors associated with screening uptake. Thirteen studies met the inclusion criteria. Findings revealed a positive association between patients' receipt of provider recommendation and uptake of breast and cervical cancer screening. Uptake was also higher among patients of female providers. Facilities with flexible appointment times and reminders had higher mammography and Pap test uptake. Similarly, greater organizational commitment to quality and performance had higher breast and cervical cancer screening rates. Knowledge provided in this review could be used in future research to inform the development of public health policy and clinical programs to improve screening uptake.

Small-area spatio-temporal analyses of participation rates in the mammography screening program in the city of Dortmund (NW Germany)

Background

The population-based mammography screening program (MSP) was implemented by the end of 2005 in Germany, and all women between 50 and 69 years are actively invited to a free biennial screening examination. However, despite the expected benefits, the overall participation rates range only between 50 and 55 %. There is also increasing evidence that belonging to a vulnerable population, such as ethnic minorities or low income groups, is associated with a decreased likelihood of participating in screening programs. This study aimed to analyze in more detail the intra-urban variation of MSP uptake at the neighborhood level (i.e. statistical districts) for the city of Dortmund in northwest Germany and to identify demographic and socioeconomic risk factors that contribute to non-response to screening invitations.

Methods

The numbers of participants by statistical district were aggregated over the three periods 2007/2008, 2009/2010, and 2011/2012. Participation rates were calculated as numbers of participants per female resident population averaged over each 2-year period. Bayesian hierarchical spatial models extended with a temporal and spatio-temporal interaction effect were used to analyze the participation rates applying integrated nested Laplace approximations (INLA). The model included explanatory covariates taken from the atlas of social structure of Dortmund.

Results

Generally, participation rates rose for all districts over the time periods. However, participation was persistently lowest in the inner city of Dortmund. Multivariable regression analysis showed that migrant status and long-term unemployment were associated with significant increases of non-attendance in the MSP.

Conclusion

Low income groups and immigrant populations are clustered in the inner city of Dortmund and the observed spatial pattern of persistently low participation in the city center is likely linked to the underlying socioeconomic gradient. This corresponds with the findings of the ecological regression analysis manifesting socioeconomically deprived neighborhoods as risk factors for low attendance in the MSP. Spatio-temporal surveillance of participation in cancer screening programs may be used to identify spatial inequalities in screening uptake and plan spatially focused interventions.

Does the Neighborhood Area of Residence Influence Non-Attendance in an Urban Mammography Screening Program? A Multilevel Study in a Swedish City

BACKGROUND AND AIM

The public health impact of population-based mammography screening programs depends on high participation rates. Thus, monitoring participation rates, as well as understanding and considering the factors influencing attendance, is important. With the goal to acquire information on the appropriate level of intervention for increasing screening participation our study aimed to (1) examine whether, over and above individual factors, the neighborhood of residence influences a woman's mammography non-attendance, and (2) evaluate, whether knowing a woman's neighborhood of residence would be sufficient to predict non-attendance.

METHODS

We analyze all women invited to mammography screening in 2005-09, residing in the city of Malmö, Sweden. Information regarding mammography screening attendance was linked to data on area of residence, demographic and socioeconomic characteristics available from Statistics Sweden. The influence of individual and neighborhood factors was assessed by multilevel logistic regression analysis with 29,901 women nested within 212 neighborhoods.

RESULTS

The prevalence of non-attendance among women was 18.3%. After adjusting for individual characteristics, the prevalence in the 212 neighborhoods was 3.6%. Neighborhood of residence had little influence on non-attendance. The multilevel analysis indicates that 8.4% of the total individual differences in the propensity of non-attendance were at the neighborhood level. However, when adjusting for specific individual characteristics this general contextual effect decreased to 1.8%. This minor effect was explained by the sociodemographic characteristic of the neighborhoods. The discriminatory accuracy of classifying women according to their non-attendance was 0.747 when considering only individual level variables, and 0.760 after including neighborhood level as a random effect.

CONCLUSION

Our results suggest that neighborhoods of residence in Malmö, Sweden (as defined by small-area market statistics (SAMS) areas) do not condition women's participation in population based mammography screening. Thus, interventions should be directed to the whole city and target women with a higher risk of non-attendance.

Geographic Access to Mammography and Its Relationship to Breast Cancer Screening and Stage at Diagnosis: A Systematic Review

INTRODUCTION

A review was conducted to summarize the current evidence and gaps in the literature on geographic access to mammography and its relationship to breast cancer-related outcomes.

METHODS

Ovid, Medline, and PubMed were searched for articles published between January 1, 2000, and April 1, 2013, using Medical Subject Headings and key terms representing geographic accessibility and breast cancer-related outcomes. Owing to a paucity of breast cancer treatment and mortality outcomes meeting the criteria (N = 6), outcomes were restricted to breast cancer screening and stage at diagnosis. Studies included one or more of the following types of geographic accessibility measures: capacity, density, distance, and travel time. Study findings were grouped by outcome and type of geographic measure.

RESULTS

Twenty-one articles met the inclusion criteria. Fourteen articles included stage at diagnosis as an outcome, five included mammography use, and two included both. Geographic measures of mammography accessibility varied widely across studies. Findings also varied, but most articles found either increased geographic access to mammography associated with increased use and decreased late-stage at diagnosis or no association.

CONCLUSION

The gaps and methodologic heterogeneity in the literature to date limit definitive conclusions about an underlying association between geographic mammography access and breast cancer-related outcomes. Future studies should focus on the development and application of more precise and consistent measures of geographic access to mammography.

Is Availability of Mammography Services at Federally Qualified Health Centers Associated with Breast Cancer Mortality-to-Incidence Ratios? An Ecological Analysis

OBJECTIVE

Mammography is the most effective method to detect breast cancer in its earliest stages, reducing the risk of breast cancer death. We investigated the relationship between accessibility of mammography services at Federally Qualified Health Centers (FQHCs) and mortality-to-incidence ratio (MIR) of breast cancer in each county in the United States.

METHODS

County-level breast cancer mortality and incidence rates in 2006-2010 were used to estimate MIRs. We compared breast cancer MIRs based on the density and availability of FQHC delivery sites with or without mammography services both in the county and in the neighboring counties.

RESULTS

The relationship between breast cancer MIRs and access to mammography services at FQHCs differed by race and county of residence. Breast cancer MIRs were lower in counties with mammography facilities or FQHC delivery sites than in counties without a mammography facility or FQHC delivery site. This trend was stronger in urban counties (p=0.01) and among whites (p=0.008). Counties with a high density of mammography facilities had lower breast cancer MIRs than other counties, specifically in urban counties (p=0.01) and among whites (p=0.01). Breast cancer MIR for blacks was the lowest in counties having mammography facilities; and was highest in counties without a mammography facility within the county or the neighboring counties (p=0.03).

CONCLUSIONS

Mammography services provided at FQHCs may have a positive impact on breast cancer MIRs. Expansion of services provided at the FQHCs and placement of FQHCs in additional underserved areas might help to reduce cancer disparities in the United States.

Tobacco retailer proximity and density and nicotine dependence among smokers with serious mental illness

OBJECTIVES

We examined the density and proximity of tobacco retailers and associations with smoking behavior and mental health in a diverse sample of 1061 smokers with serious mental illness (SMI) residing in the San Francisco Bay Area of California.

METHODS

Participants' addresses were geocoded and linked with retailer licensing data to determine the distance between participants' residence and the nearest retailer (proximity) and the number of retailers within 500-meter and 1-kilometer service areas (density).

RESULTS

More than half of the sample lived within 250 meters of a tobacco retailer. A median of 3 retailers were within 500 meters of participants' residences, and a median of 12 were within 1 kilometer. Among smokers with SMI, tobacco retailer densities were 2-fold greater than for the general population and were associated with poorer mental health, greater nicotine dependence, and lower self-efficacy for quitting.

CONCLUSIONS

Our findings provide further evidence of the tobacco retail environment as a potential vector contributing to tobacco-related disparities among individuals with SMI and suggest that this group may benefit from progressive environmental protections that restrict tobacco retail licenses and reduce aggressive point-of-sale marketing.

Geographic variations in access and utilization of cancer screening services: examining disparities among American Indian and Alaska Native Elders

Background

Despite recommendations for cancer screening for breast and colorectal cancer among the Medicare population, preventive screenings rates are often lower among vulnerable populations such as the small but rapidly growing older American Indian and Alaska Native (AIAN) population. This study seeks to identify potential disparities in the availability of screening services, distance to care, and the utilization of cancer screening services for Medicare beneficiaries residing in areas with a higher concentration of AIAN populations.

Methods

Using the county (n =3,225) as the level of analysis, we conducted a cross-sectional analysis of RTI International’s Spatial Impact Factor Data (2012) to determine the level of disparities for AIAN individuals. The outcomes of interest include: the presence of health care facilities in the county, the average distance in miles to the closest provider of mammography and colonoscopy (analyzed separately) and utilization of screening services (percent of adults aged 65 and older screened by county).

Results

Counties with higher concentrations of AIAN individuals had greater disparities in access and utilization of cancer screening services. Even after adjusting for income, education, state of residence, population 65 and older and rurality, areas with higher levels of AIAN individuals were more likely to see disparities with regard to health care services related to mammograms (p ≤ .05; longer distance, lower screening) and colonoscopies (p ≤ .05; longer distance, lower screening).

Conclusions

These findings provide evidence of a gap in service availability, utilization and access facing areas with higher levels of AIAN individuals throughout the US. Without adequate resources in place, these areas will continue to have less access to services and poorer health which will be accelerated as the population of older adults grows.

Association between individual and geographic factors and nonadherence to mammography screening guidelines

BACKGROUND

This study investigates factors that are associated with nonadherence to mammography screening guidelines in Utah, a state where mammography screening rates have remained consistently lower than national averages.

METHODS

We examined data on reported mammography use among women aged 40-74 years from the 2008 and 2010 Utah Behavioral Risk Factor Surveillance System (n=5,197, weighted n=417,064). Logistic regression models were used to estimate the effects of individual-level and geographic (travel time to nearest mammography facility, geographic accessibility, and rural/urban residence) factors on the odds of a woman not reporting receiving a mammogram in the last 2 years.

RESULTS

In 2008 and 2010, a disproportionate number of women aged 40-49 (43.1%, 95% confidence interval [CI] 39.9%-46.3%) reported not receiving a mammogram within the last 2 years compared to women 50-74 (26.8%, 95% CI 24.9%-28.7%). None of the geographic factors were significant predictors of screening adherence. Based on covariate adjusted models, statistically significant (p<0.05) factors associated with increased odds of not receiving mammogram within the last 2 years included not having a regular physician, no health insurance, being aged 40-49, income less than $25,000, and the presence of three or more children in the home.

CONCLUSION

Mammography screening efforts in Utah should focus on improving access to insurance or a regular source of health care. Future research should also consider how best to address extreme time demands and competing priorities that present potential barriers for women with large families, resulting in lower screening levels among these women.

Geographic disparities in mammography capacity in the South: a longitudinal assessment of supply and demand

OBJECTIVE

Studies have shown that there is sufficient availability of mammography; however, little is known about geographic variation in capacity. The purpose of this study was to determine the locations and extent of over/undersupply of mammography in 14 southern states from 2002 to 2008.

DATA SOURCES

Mammography facility data were collected from the U.S. Food and Drug Administration (FDA). Population estimates, used to estimate the potential demand for mammography, were obtained from GeoLytics Inc.

STUDY DESIGN

Using the two-step floating catchment area method, we calculated spatial accessibility at the block group level and categorized the resulting index to represent the extent of under/oversupply relative to the potential demand.

PRINCIPAL FINDINGS

Results show decreasing availability of mammography over time. The extent of over/undersupply varied significantly across the South. Reductions in capacity occurred primarily in areas with an oversupply of machines, resulting in a 68 percent decrease in the percent of women living in excess capacity areas from 2002 to 2008. The percent of women living in poor capacity areas rose by 10 percent from 2002 to 2008.

CONCLUSIONS

Our study found decreasing mammography availability and capacity over time, with substantial variation across states. This information can assist providers and policy makers in their business planning and resource allocation decisions.

Urban sprawl, obesity, and cancer mortality in the United States: cross-sectional analysis and methodological challenges

BACKGROUND

Urban sprawl has the potential to influence cancer mortality via direct and indirect effects on obesity, access to health services, physical activity, transportation choices and other correlates of sprawl and urbanization.

METHODS

This paper presents a cross-sectional analysis of associations between urban sprawl and cancer mortality in urban and suburban counties of the United States. This ecological analysis was designed to examine whether urban sprawl is associated with total and obesity-related cancer mortality and to what extent these associations differed in different regions of the US. A major focus of our analyses was to adequately account for spatial heterogeneity in mortality. Therefore, we fit a series of regression models, stratified by gender, successively testing for the presence of spatial heterogeneity. Our resulting models included county level variables related to race, smoking, obesity, access to health services, insurance status, socioeconomic position, and broad geographic region as well as a measure of urban sprawl and several interactions. Our most complex models also included random effects to account for any county-level spatial autocorrelation that remained unexplained by these variables.

RESULTS

Total cancer mortality rates were higher in less sprawling areas and contrary to our initial hypothesis; this was also true of obesity related cancers in six of seven U.S. regions (census divisions) where there were statistically significant associations between the sprawl index and mortality. We also found significant interactions (p < 0.05) between region and urban sprawl for total and obesity related cancer mortality in both sexes. Thus, the association between urban sprawl and cancer mortality differs in different regions of the US.

CONCLUSIONS

Despite higher levels of obesity in more sprawling counties in the US, mortality from obesity related cancer was not greater in such counties. Identification of disparities in cancer mortality within and between geographic regions is an ongoing public health challenge and an opportunity for further analytical work identifying potential causes of these disparities. Future analyses of urban sprawl and health outcomes should consider exploring regional and international variation in associations between sprawl and health.

Provincial screening rates for chronic diseases of lifestyle, cancers and HIV in a health-insured population

BACKGROUND

Screening for asymptomatic diseases can reduce the burden of morbidity and mortality in all population groups. There is widespread geographical variation in the quality of care. Few data are available on national screening rates in South Africa and how these vary across the provinces.

OBJECTIVE

To examine screening rates for chronic diseases of lifestyle (CDL), HIV and cancer in a privately insured population for a single insurer across all nine provinces in South Africa, and to determine whether or not there are any differences between the provinces.

METHOD

Screening rates were calculated as the proportion of eligible members who had received screening tests during 2011 in each province. Mean screening rates were compared between Gauteng and the other eight provinces.

RESULTS

Nationwide screening rates were 20.5% for CDL, 8.2% for HIV and 31.9% for cancer. Despite similar insurance coverage, screening rates ranged from 0.3% to 0.95% lower in other provinces compared with Gauteng. Of all the provinces, Gauteng had the highestannual screening rates for CDL, breast cancer, prostate cancer and HIV (p < 0.001), while the Western Cape had the highest rate for cervical cancer (p < 0.001).

CONCLUSION

There is much variation in preventive care utilisation across the provinces within this health-insured population. Provinces with more abundant healthcare resources have higher screening rates. Further research is required to understand the reasons for the variation, given equal payment access.

The joint effects of census tract poverty and geographic access on late-stage breast cancer diagnosis in 10 US States

This study evaluated independent and joint effects of census tract (CT) poverty and geographic access to mammography on stage at diagnosis for breast cancer. The study included 161,619 women 40+ years old diagnosed with breast cancer between 2004 -2006 in ten participating US states. Multilevel logistic regression was used to estimate the odds of late-stage breast cancer diagnosis for the entire study population and by state. Poverty was independently associated with late-stage in the overall population (poverty rates >20% OR=1.30, 95% CI=1.26- 1.35) and for 9 of the 10 states. Geographic access was not associated with late-stage diagnosis after adjusting for CT poverty. State-specific analysis provided little evidence that geographic access was associated with breast cancer stage at diagnosis, and after adjusting for poverty, geographic access mattered in only 1 state. Overall, compared to women with private insurance, the adjusted odds ratios for late stage at diagnosis among women with either no insurance, Medicaid, or Medicare were 1.80 (95% CI = 1.65, 1.96), 1.75 (95% CI = 1.68, 1.84), and 1.05 (95% CI 1.01, 1.08), respectively. Although geographic access to mammography was not a significant predictor of late-stage breast cancer diagnosis, women in high poverty areas or uninsured are at greatest risk of being diagnosed with late-stage breast cancer regardless of geographic location and may benefit from targeted interventions.

Regional factors associated with participation in the national health screening program: a multilevel analysis using national data

High participation rates are important for maximizing the effects of a health screening program. Previous studies have suggested that individual or regional characteristics have effects on health behaviors. In this study, we investigated the determinants of participation in the National Screening Program for Transitional Ages by simultaneously analyzing individual and area-level factors by multilevel analysis. A total of 1,081,216 subjects, aged 40 and 66 yr and nested in 254 areas, were included. There was a significant variation in participation rates across the areas even after adjusting for individual and area-level variables. Among the individual-level variables, increasing age, sex, higher income, and mild disability grade were associated with a higher participation rate. In urban areas, the 40-yr-old group had higher participation rates than the 66-yr-old group. Deprived areas had significantly high participation rates for both age groups. The number of screening centers per 1,000 inhabitants had no significant effect on participation in the screening program. In conclusion, regional characteristics are associated with participation rates independent of personal features and regional factors have differential effects with respect to age. A multi-dimensional approach is recommended to promote participation in health screening programs.

Comparing GIS-based measures in access to mammography and their validity in predicting neighborhood risk of late-stage breast cancer

Background

Assessing neighborhood environment in access to mammography remains a challenge when investigating its contextual effect on breast cancer-related outcomes. Studies using different Geographic Information Systems (GIS)-based measures reported inconsistent findings.

Methods

We compared GIS-based measures (travel time, service density, and a two-Step Floating Catchment Area method [2SFCA]) of access to FDA-accredited mammography facilities in terms of their Spearman correlation, agreement (Kappa) and spatial patterns. As an indicator of predictive validity, we examined their association with the odds of late-stage breast cancer using cancer registry data.

Results

The accessibility measures indicated considerable variation in correlation, Kappa and spatial pattern. Measures using shortest travel time (or average) and service density showed low correlations, no agreement, and different spatial patterns. Both types of measures showed low correlations and little agreement with the 2SFCA measures. Of all measures, only the two measures using 6-timezone-weighted 2SFCA method were associated with increased odds of late-stage breast cancer (quick-distance-decay: odds ratio [OR] = 1.15, 95% confidence interval [CI] = 1.01–1.32; slow-distance-decay: OR = 1.19, 95% CI = 1.03–1.37) after controlling for demographics and neighborhood socioeconomic deprivation.

Conclusions

Various GIS-based measures of access to mammography facilities exist and are not identical in principle and their association with late-stage breast cancer risk. Only the two measures using the 2SFCA method with 6-timezone weighting were associated with increased odds of late-stage breast cancer. These measures incorporate both travel barriers and service competition. Studies may observe different results depending on the measure of accessibility used.

Disparities in routine breast cancer screening for Medicaid managed care members with a work-limiting disability

OBJECTIVE

Examine disparities in routine mammography for women who qualify for Medicaid, because of a work-limiting disability.

METHODS

Individual-level data were obtained for women enrolled in Massachusetts Medicaid Managed Care plans who met the 2007 Healthcare Effectiveness Data and Information Set (HEDIS) criteria for the breast cancer screening measure (n=35,171). Disability status was determined from Medicaid eligibility records. Mammography screening was modeled using multivariate logistic regression. Separate models for women with and without a disability were also estimated.

RESULTS

Although unadjusted breast cancer screening rates were roughly equal for women with and without disability, after adjusting for confounders disability status had a significant negative association with screening mammography (OR=0.74; p<0.0001). Living farther from a mammography facility or having a diagnosis of domestic violence reduced the odds of screening for women with disabilities, but not for other women. Having a higher illness burden was more detrimental to screening for women with a disability than for those without. Both groups benefited similarly from the first 26 ambulatory care visits, but the impact of additional visits on screening was much larger among women with disabilities.

CONCLUSION

Nationwide, rates of routine mammography for Medicaid managed care plans averaged below 50% in 2006. Given that a majority of eligible women served by Medicaid have disabilities, and studies have shown that women with disabilities are more likely to be diagnosed with late stage disease, a focus on improving rates of screening for women with disabilities is overdue.

Time and distance barriers to mammography facilities in the Atlanta metropolitan area

To a great extent, research on geographic accessibility to mammography facilities has focused on urban-rural differences. Spatial accessibility within urban areas can nonetheless pose a challenge, especially for minorities and low-income urban residents who are more likely to depend on public transportation. To examine spatial and temporal accessibility to mammography facilities in the Atlanta metropolitan area by public and private transportation, we built a multimodal transportation network model including bus and rail routes, bus and rail stops, transfers, walk times, and wait times. Our analysis of travel times from the population-weighted centroids of the 282 census tracts in the 2-county area to the nearest facility found that the median public transportation time was almost 51 minutes. We further examined public transportation travel times by levels of household access to a private vehicle. Residents in tracts with the lowest household access to a private vehicle had the shortest travel times, suggesting that facilities were favorably located for women who have to use public transportation. However, census tracts with majority non-Hispanic black populations had the longest travel times for all levels of vehicle availability. Time to the nearest mammography facility would not pose a barrier to women who had access to a private vehicle. This study adds to the literature demonstrating differences in spatial accessibility to health services by race/ethnicity and socioeconomic characteristics. Ameliorating spatial inaccessibility represents an opportunity for intervention that operates at the population level.

The role of public health and how boundary analysis can provide a tool for public health investigations: the public health perspective

The rapidly expanding capabilities to analyze geocoded data are opening many possibilities to provide revolutionary improvements in the ability to monitor health events over time and space. The role of public health and what science based public health intervention means is reviewed. The type of information that is useful to public health planners is discussed. How geospatial analysis fits in with the process of developing public health programs and how the public health field can use these advances in analytical techniques, associated software and available geocoded data is discussed. The value of boundary analysis as an analytical tool is assessed from the public health perspective. Why the ability to determine geographically associated event clusters and to identify the boundaries of clusters, independent of any predetermined polygon, establishes the best information possible for assessing health event data, planning interventions and monitoring the outcomes of intervention efforts is discussed.

Prevalence and correlates of recent and repeat mammography among California women ages 55-79

OBJECTIVE

Data on repeat mammography rates are less available than for recent screening. Two large, population-based state surveys provide the opportunity to investigate repeat and recent mammography prevalence and correlates among California's diverse population.

METHODS

Data were from women aged 55-79, using the 2001 and 2005 California Health Interview Surveys. The study assessed the prevalence and correlates of recent mammography (within the past two years) and repeat mammography (mammogram within the past two years and 3-11 mammograms within the past six years).

RESULTS

Prevalence was 82.4% (recent) and 73.8% (repeat) in 2001, and 87.1% (recent) and 77.5% (repeat) in 2005. Correlates of lower rates were insurance status, no usual source of care, being a smoker, age 65-79, being Asian with no English proficiency, being never married, and lower absolute risk for breast cancer. Especially low ratios of repeat-to-recent mammography existed for the uninsured, and those using the emergency room or with no source of care. Unexpected findings in which unadjusted results were inconsistent with multivariable adjusted results occurred for Latinas with no English proficiency and women at 200-299% of poverty level.

CONCLUSIONS

Several groups of women in California remain at-risk of lower mammography utilization. However, investigators should also be alert for instances where multivariable analyses seem particularly discrepant with crude rates.

Continuity of care and colorectal cancer screening by Vietnamese American patients

BACKGROUND

Colorectal cancer (CRC) screening rates among Asian Americans are 30-50% lower than among Whites. Using practice management and electronic medical records data from a community health center, we examined the association of CRC screening with continuity of care and comorbidity. These variables have not previously been studied in Asian American and limited-English proficient populations.

METHODS

After obtaining IRB approval, we extracted data in 2009 on age-eligible Vietnamese patients who had one or more clinic visits in the prior 24 months. Our analysis examined associations between CRC screening (per current US Preventive Services Task Force guidelines) and clinic site, demographics, insurance status, continuity of care, comorbidities, and provider characteristics.

RESULTS

We identified a total of 1,016 eligible patients (604 at Clinic 1 and 412 at Clinic 2). Adherence to CRC screening was lower for patients who were male; lacked insurance; had only one medical visit in the past 12 months; and had no assigned primary care provider. Our multivariable models showed higher screening rates among patients who were female; had public health insurance; and had more than one medical visit in the past 12 months, regardless of high or low continuity of care.

CONCLUSIONS

We found no association between higher continuity of care and CRC screening. Additional primary care systems research is needed to guide cancer screening interventions for limited-English proficient patients.

Breast cancer care in the Canada and the United States: ecological comparisons of extremely impoverished and affluent urban neighborhoods

This study examined the differential effect of extreme impoverishment on breast cancer care in urban Canada and the United States. Ontario and California registry-based samples diagnosed between 1998 and 2000 were followed until 2006. Extremely poor and affluent neighborhoods were compared. Poverty was associated with non-localized disease, surgical and radiation therapy (RT) waits, non-receipt of breast conserving surgery, RT and hormonal therapy, and shorter survival in California, but not in Ontario. Extremely poor Ontario women were consistently advantaged on care indices over their California counterparts. More inclusive health insurance coverage in Canada seems the most plausible explanation for such Canadian breast cancer care advantages.