Service Area Level Research Articles

Unregulated drinking water contaminants and adverse birth outcomes in Virginia

Unregulated drinking water contaminants and adverse birth outcomes in Virginia

A Study of Regional Rural Banks : The Conundrum of Managing Inclusion with Sustainability

Regional rural banks (RRBs) were created with the vision to expand banking services to the underprivileged population in rural areas sustainably and effectively. However, after a decade of inception, such institutionsfinancial viability and survival became questionable, which posed a serious concern for policymakers. As a result, the Government of India and its regulators initiated various policies in the late 1990s to make these institutions financially viable and self-sustainable in the long run. These policy interventions have successfully transformed the financial health of RRBs to some extent. However, in this process, it was widely discussed that the RRBs were moving away from their original mandate. However, no detailed study has been published so far to investigate this dimension. This paper tried to bridge this gap by exploring the performance of RRBs with respect to the objectives for which they were incorporated through evidence based on data. This is the first study that provides a comparison of the performance of RRBs with other banks at the service area level. The study observed that RRBs have remained true to their original mandate and are still doing relatively better in comparison to other commercial banks in their area of operation.

Examining the association between safe drinking water act violations and adverse birth outcomes in Virginia

In 1974, the United States established the Safe Drinking Water Act (SDWA) to protect consumers from potential exposure to drinking water contaminants associated with health risks. Each contaminant is assigned a health-based standard meant to reflect the maximum level at which an adverse human health outcome is unlikely; measurements beyond that level have greater potential to result in adverse health outcomes. Although there is extensive research on human health implications following water contaminant exposure, few studies have specifically examined associations between fetal health and municipal drinking water violations. Therefore, the objective of this study is to assess whether SDWA drinking water violations are associated with fetal health outcomes, including preterm birth (PTB), low birth weight (LBW), and term-low birth weight (tLBW), in the Commonwealth of Virginia.Singleton births (n = 665,984) occurring between 2007 and 2015 in Virginia were geocoded and assigned to a corresponding estimated water service area. Health-based (HB) and monitoring and reporting (MR) violations for 12 contaminants were acquired from the US EPA Safe Drinking Water Information System, with exposure defined at the approximate service area level to limit exposure misclassification. A logistic regression model for each birth outcome assessed potential relationships with SDWA violations.When examining the association between individual MR violations and birth outcomes, Nitrate-Nitrite (OR = 1.10; 95% CI = 1.02, 1.18, P = 0.01) was positively associated with PTB and the total coliform rule was negatively associated with tLBW (OR = 0.93; 95% CI = 0.87, 1.00, P = 0.04). These findings indicate that a lack of regular monitoring and reporting by water providers (resulting in monitoring and reporting violations) may be concealing health-based violations as these health concerns cannot be revealed without testing, suggesting a need for additional technical, managerial, and financial support to enable often-underfunded water systems to adhere to monitoring and reporting requirements meant to protect public health.

Investigation of pedestrian and bicyclist safety in public transportation systems

IntroductionUnderstanding the crash risk factors associated with pedestrians and bicyclists is vital to promoting pedestrian- and bicycle-friendly communities and ensuring the sustainability of the transportation system. Transit stations perform as important mode transfer locations for bicyclists and pedestrians. However, past studies on contributing factors to pedestrian and bicycle crash in transit station service areas are limited. This study develops a model to guide the prioritization of areas for bicyclist and pedestrian safety improvement. MethodThis study analyzes pedestrian and bicyclist safety in subway station service areas using publicly available crash data from New York City (NYC) area. For the model development, various subway station and built-environment characteristics related variables were aggregated to the subway station service area level. Spatial regression and random parameter models were developed to account for spatial heterogeneity and spatial dependency in the crash data. Performance measures of the developed models showed that the Semi-Parametric Geographically Weighted Poisson Regression (S-GWPR) model better explained the variation in the crash frequency. ResultsThe results showed that subway stations in NYC with high ridership were positively associated with pedestrian and bicycle crashes. The number of bus stops in a subway station service area was also positively associated with pedestrian and bicycle crashes. This study also found that additional bike lanes can reduce bicycle-involved crashes. ConclusionAreas surrounding transit stations, where pedestrian and bicyclist activities are usually high, require special attention to deploy appropriate safety countermeasures. The findings of this study suggest that cities can install more bike lanes to promote the safety of bicyclists. Using the results of this study, traffic safety planners can prioritize areas for the implementation of safety countermeasures in NYC.

Improving economic conditions associated with care pattern and cost changes

Background: Low economic prosperity is associated with worse health and health outcomes. Dramatic increases in prosperity have been associated with reductions in mortality rates. Methods: We conducted a retrospective serial cross-sectional study of Medicare beneficiaries aged 65 and older who were enrolled in Medicare Parts A and B each year, 2003–2015. We examined local economic conditions in 2000 and 2015 at the Dartmouth Atlas-defined Hospital Service Area level. For quintiles of local economic distress in 2000, and for areas that experienced dramatic improvement or deterioration in local economic distress, we calculated per-capita rates of avoidable admissions, receipt of appropriate primary care services, elective surgery utilization, and total Medicare Parts A and B healthcare spending Results: Beneficiaries who lived in the lowest-prosperity areas had higher rates of avoidable admissions, lower rates of appropriate primary care services, higher rates of elective surgeries, and higher overall healthcare spending than those living in the highest-prosperity areas. Dramatic improvement in local economic conditions was associated with adoption of healthcare utilization closely resembling those of the most-prosperous areas and divergent from that of areas that did not see improvement; further, the most-prosperous areas had healthcare consumption patterns that were “immune” to economic decline. Conclusions: Our findings suggest that improving local economic conditions could have healthcare utilization and quality implications. Policymakers should consider improved healthcare quality and reduced avoidable and potentially unnecessary high-cost care as potential returns on investment in improving local economic conditions, while being mindful of potential increases in care costs.

Modeling schistosomiasis spatial risk dynamics over time in Rwanda using zero-inflated Poisson regression

The recorded clinical cases of S. mansoni at primary health facility level contain an excessive number of zero records. This could mean that no S. mansoni infection occurred (a true zero) in the health facility service area but it could also that at least one infection occurred but none were reported or diagnosed (a false zero). Standard statistical analysis, using exploratory or confirmatory spatial regression, fail to account for this type of data insufficiency. This study developed a zero-inflated Poisson model to explore the spatiotemporal variation in schistosomiasis risk at a fine spatial scale. We used environmental data generated at primary health facility service area level as explanatory variables affecting transmission risk. Identified risk factors were subsequently used to project the spatial variability of S. mansoni infection risk for 2050. The zero-inflated Poisson model shows a considerable increase of relative risk of the schistosomiasis over one decade. Furthermore, the changes between the risk in 2009 and forecasted risk by 2050 indicated both persistent and emerging areas with high relative risk of schistosomiasis infection. The risk of schistosomiasis transmission is 69%, 29%, and 50% higher in areas with rice cultivation, proximity to rice farms, and proximity to a water body respectively. The prediction and forecasting maps provide a valuable tool for monitoring schistosomiasis risk in Rwanda and planning future disease control initiatives in wetland ecosystem development context.

Kidney nonprocurement in solid organ donors in the United States.

There are limited data on the nonprocurement of kidneys from solid organ donors. Analysis of Standard Transplant Analysis and Research files was undertaken on all deceased donors in the United States with at least 1 solid organ recovered. From 2000 to 2018, 21731 deceased donor kidneys (averaging 1144 kidneys per year) were not procured. No kidneys were procured from 8% of liver donors, 3% of heart donors, and 3% of lung donors. Compared to donors with all kidneys procured, those with none procured were older and more likely obese, black, hypertensive, diabetic, hepatitis C positive, smokers, Public Health Service - Increased Risk designated, deceased after cardiac death, or deceased after cerebrovascular accident. Although these donors had lower quality kidneys (median Kidney Donor Risk Index (interquartile range) 1.9 (1.0) vs 1.2 (0.7)), there was substantial overlap in quality between nonprocured and procured kidneys. Nearly one third of nonprocurements were attributed to donor history. Donors with elevated terminal creatinine likely resulting from acute kidney injury (AKI) had higher odds of kidney nonprocurement. Nonprocurement odds varied widely across Organ Procurement and Transplantation Network regions, with a positive correlation between donor kidney nonprocurements and kidney discards at the donationservice area level. These findings suggest current discard rates underestimate the underutilization of deceased donor kidneys and more research is needed to optimize safe procurement and utilization of kidneys from donors with AKI.

Higher Density of Primary Care Facilities Is Inversely Associated with Ischemic Heart Disease Mortality, but Not with Stroke Mortality: A Japanese Secondary Medical Service Area Level Ecological Count Data.

Poor accessibility to physicians might be linked to the inadequate control of cardiovascular risk factors. The aim of this study was to investigate whether the accessibility of primary care physicians was related to a lower incidence of ischemic heart disease and stroke mortality via ecological data analyses of both primary care facility density and internal physician density. The unit of observation was the Japanese secondary medical service area, the basic unit for healthcare planning and administration. A primary care facility was defined as a clinic or medical institution with less than 200 inpatient beds, whose specialty included internal medicine. The number of primary care facilities per 10,000 population and the number of internal physicians per 10,000 population were used as explanatory variables. Bayesian hierarchical models were used to analyze the relative risks (RR) of primary care facility density and internal physician density using the socioeconomic confounders of designated emergency hospitals, natural log-transformed population density, birth rate, secondary and tertiary industrial workers, and taxable income. In multivariate models for ischemic heart disease mortality, primary care facility density was significantly related to the total population (RR = 0.986, 95% credible interval [CrI]: 0.979-0.993), men (RR = 0.988, 95% CrI: 0.981-0.996), and women (RR = 0.986, 95% CrI: 0.979-0.993). No significant results were obtained for internal physician density. In the multivariate models for stroke mortality, neither primary care facility density nor internal physician density showed any significant effects. Increasing primary care facility density may reduce ischemic heart disease mortality.

Accountable Care Organizations Serving Deprived Communities Are Less Likely to Share in Savings.

Primary care physicians are increasingly participating in accountable care organizations (ACOs). While prior studies have identified ACO and patient characteristics associated with savings, none have examined characteristics of the communities served by ACOs. Our objective was to assess the relationship between an ACO's service area characteristics and its savings rate. In this cross-sectional study, we used the Centers for Medicare and Medicaid Services 2014 Medicare Shared Savings Program ACO Provider and Beneficiary, and Public Use Files to identify ACO and beneficiary characteristics. We used the American Community Survey to measure community deprivation at the ACO service area-level by using the social deprivation index. The outcome of interest was the ACO savings rate. We conducted bivariate analyses and regressions, adjusting for ACO organization and beneficiary characteristics. Our sample consisted of 320 ACOs participating in the Shared Savings Plan. The savings rate for ACOs serving the most deprived communities was 1.19% compared with 1.14% for those serving the least deprived. Adjusting for ACO and beneficiary characteristics, however, ACOs serving the most deprived had a savings rate that was 2.3 percentage points lower than those serving the least deprived. ACOs serving deprived communities generate less savings. These findings are important to primary care practices, payers, and policy makers anticipating continued ACO expansion, if population health is to be achieved equitably.

Children's Mental Health Need and Expenditures in Ontario: Findings from the 2014 Ontario Child Health Study.

Objective:To estimate the alignment between the Ontario Ministry of Children and Youth Services (MCYS) expenditures for children’s mental health services and population need, and to quantify the value of adjusting for need in addition to population size in formula-based expenditure allocations. Two need definitions are used: “assessed need,” as the presence of a mental disorder, and “perceived need,” as the subjective perception of a mental health problem.Methods:Children’s mental health need and service contact estimates (from the 2014 Ontario Child Health Study), expenditure data (from government administrative data), and population counts (from the 2011 Canadian Census) were combined to generate formula-based expenditure allocations based on 1) population size and 2) need (population size adjusted for levels of need). Allocations were compared at the service area and region level and for the 2 need definitions (assessed and perceived).Results:Comparisons were made for 13 of 33 MCYS service areas and all 5 regions. The percentage of MCYS expenditure reallocation needed to achieve an allocation based on assessed need was 25.5% at the service area level and 25.6% at the region level. Based on perceived need, these amounts were 19.4% and 27.2%, respectively. The value of needs-adjustment ranged from 8.0% to 22.7% of total expenditures, depending on the definition of need.Conclusion:Making needs adjustments to population counts using population estimates of children’s mental health need (assessed or perceived) provides additional value for informing and evaluating allocation decisions. This study provides much-needed and current information about the match between expenditures and children’s mental health need.

Perioperative Intravesical Chemotherapy for Patients WithNon–Muscle-invasive Bladder Cancer: Understanding the Extent of and Sources of Variation in Guideline-recommended Use

ObjectiveTo examine intravesical chemotherapy (IVC) use according to non–muscle-invasive bladder cancer patient disease risk, and the contributions of multilevel factors to variation in proficient use among patients with low-intermediate disease. MethodsThis study included 988 patients diagnosed with non–muscle-invasive bladder cancer in an integrated health system in Northern California from 2015-2017. We calculated IVC receipt by disease risk, and among patients with low-intermediate risk disease, assessed the relationship between multilevel factors and IVC receipt using a logistic regression model with random intercepts for provider and service area, and patient-, provider-, and service area-level fixed effects. We further assessed the association of provider- and service area-level factors with IVC use by examining intraclass correlation coefficients. ResultsSimilar proportions of low-intermediate (36%) and high-risk (34%) patients received IVC. In the multivariate analysis, including low-intermediate risk patients, service area volume was strongly and statistically significantly associated with IVC use (adjusted odds ratio, high- vs low-volume: 0.08, 95% Confidence Interval: 0.01-0.58). Provider- and service area-level intraclass correlation coefficients were large, (38%, P = .0009 and 39% P = .03, respectively) indicating that much of the variance in IVC use was explained by factors at these levels. ConclusionOur findings highlight opportunities to improve proficient use of IVC. Future research should assess provider- and practice-level barriers to IVC use among low-intermediate risk patients.

Correlation Between Kidney Transplant Outcome Metrics and Waitlist Metrics.

Currently the Organ Procurement and Transplant Network and CMS use 1-year patient and graft survival as metrics to flag transplant programs.1 Waitlist and longer-term posttransplant outcomes are publicly reported and have been suggested as regulatory metrics, but both involve factors outside the transplant center. We tested how well the current survival metrics capture these other dimensions. We evaluated transplant programs between 2011 and 2016 using hierarchical regression based on 2017 Scientific Registry of Transplant Recipient risk adjustment models.2,3 We used mixed-effect Poisson regression with center and donor service area–level random intercepts for waitlist metrics and center-level shared frailty Cox regression for posttransplant metrics. We ranked centers' risk-adjusted performance from 1 (best) to N (worst) based on center-level random effects from these models and correlated 1-year posttransplant outcomes with 3-year posttransplant outcomes, deceased donor kidney transplant rates, and waitlist mortality. One- and 3-year graft loss were moderately correlated (r = 0.75), as were 1- and 3-year patient mortalities (r = 0.74) (Figure 1). However, 1-year graft loss and mortality correlated poorly with deceased donor kidney transplantation rate (r = 0.02, 0.14), and waitlist mortality (r = −0.23, −0.11) (Figure 1).FIGURE 1: Correlations between rankings of center-level effects (representing average expected outcome at a given center) for adult kidney transplant outcome metrics. One-year posttransplant metrics calculated using adult recipients January 1, 2014, to June 30, 2016 (N = 28847), waitlist metrics include adult waitlist registrants January 1, 2014, to June 30, 2016 (N = 187407), and 3-year metrics include adult recipients July 1, 2011 to December 31, 2013 (N = 26167). Centers that performed less than 25 transplants during the 2.5-year study periods were excluded (N = 190 for 1-year metrics, N = 188 for 3-year metrics). Center-level effects based on mixed-effect Poisson regressions (random intercepts) and Cox regressions (shared-frailty) ranked from 1 (best) to N (worst). This study used data from the SRTR. SRTR, Scientific Registry of Transplant Recipients.The high correlation between 1- and 3-year posttransplant outcomes suggests that regulation based on 1-year metrics is also representative of the longer-term patient experience. In contrast, the independence between posttransplant outcomes versus transplant rates and waitlist outcomes suggests that the underlying mechanisms are different, including the possibility that factors, such as geographic organ availability, affect transplant rates and waitlist outcomes. If these domains are to be regulated, the risk/benefit of using these metrics will require careful evaluation.

Influence of race, insurance status, and geographic access to plastic surgeons on immediate breast reconstruction rates

BackgroundThis study evaluates the rates of immediate breast reconstruction (IBR) among racial and insurance status subgroups, in the setting of a changing plastic surgeon workforce. MethodsUsing state level inpatient and ambulatory surgery data, we identified discharges for adult women who underwent mastectomy for breast cancer. This information was supplemented with plastic surgeon workforce data and aggregated to the health service area-level (HSA). Hierarchical linear models were used to risk standardized IBR rates for 8 race-payer subgroups. ResultsThe final cohort included 65,246 women treated across 67 HSAs. The plastic surgeon density per 100,000 population directly related to the IBR rate. While all subgroups saw a modest increase in IBR rates, Caucasian women with private insurance realized the largest absolute increase (46%) while African-American and Asian women with public insurance saw the smallest increase (6%). ConclusionSignificant disparities persist in the provision of IBR according to the form of insurance a patient possesses. Of heightened concern is the novel finding that even within privately insured patients, women of color have significantly lower IBR rates compared to Caucasian women.

Electronic Healthcare's Relationship With Patient Satisfaction and Communication.

Healthcare information technology (HIT) has been examined and shown to be a tool to improve patient healthcare quality. This study seeks to define the relationship between HIT applications such as computerized physician order entry, clinical decision support systems, and handheld device use and select Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) measures (doctor and nurse communication, discharge instructions, and whether the patient would highly recommend the hospital). Several control variables were used that represent the hospital level and contextual hospital service area level. The analysis had mixed results: the aforementioned HIT applications may add and support certain HCAHPS measures (Always Given Discharge Information), whereas there were no significant findings for the more interpersonal quality measures (nurse and doctor communication, recommendation). These results show that although patients may not score doctors and nurses significantly higher for their communication in hospitals that use HIT, they did receive discharge instructions significantly at a higher rate than the non-HIT hospitals.

The Impact of General Surgeon Supply on the Risk of Appendiceal Rupture in North Carolina

To determine whether individuals from surgery-specific service areas with a low supply of general surgeons (GSs) are at increased risk for ruptured appendicitis (ruptured appendicitis is an indicator of surgical access). The increased health care costs and morbidity linked to appendiceal rupture are considered preventable in most cases with timely access to surgery. Among the factors thought to affect an individual's access to surgery for appendicitis is the relative supply of GSs. The maldistribution of GSs is targeted by a Medicare bonus payment although the impact of GS supply on surgical access has yet to be fully described. Patients discharged from acute care and ambulatory surgery facilities in North Carolina from 2007 to 2009 were pooled for observational analysis. Using ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification) codes, cases were identified as ruptured or unruptured. GS shortage levels based on supply were calculated at the surgical service area level and tested for an association with an individual's risk of rupture using logistic regression. Living in a service area with less than 3 GSs per 100,000 people significantly increases the probability of rupture in individuals with appendicitis, compared with living in a service area with at least 5 GSs per 100,000. The supply of GSs does affect access to surgical services for appendicitis. Expanding on this finding, the recently instituted HPSA (health professional shortage area) surgical incentive payment from the Affordable Care Act should be evaluated closely for its effectiveness. Enhancing supply in critical shortage areas could reduce appendiceal rupture and improve surgical access more generally.

The Small Area Predictors of Ambulatory Care Sensitive Hospitalizations: A Comparison of Changes over Time

The hospital admission for ambulatory care sensitive conditions (ACSCs) is a validated indicator of impeded access to good primary and preventive care services. The authors examine the predictors of ACSC admissions in small geographic areas in two cross-sections spanning an 11-year time interval (1995–2005). Using hospital discharge data from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality for Arizona, California, Massachusetts, Maryland, New Jersey, and New York for the years 1995 and 2005, the study includes a multivariate cross-sectional design, using compositional factors describing the hospitalized populations and the contextual factors, all aggregated at the primary care service area level. The study uses ordinary least squares regressions with and without state fixed effects, adjusting for heteroscedasticity. Data is pooled over 2 years to assess the statistically significant changes in associations over time. ACSC admission rates were inversely related to the availability of local primary care physicians, and managed care was associated with declines in ACSC admissions for the elderly. Minorities, aged elderly, and percent under federal poverty level were found to be associated with higher ACSC rates. The comparative analysis for 2 years highlights significant declines in the association with ACSC rates of several factors including percent minorities and rurality. The two policy-driven factors, primary care physician capacity and Medicare-managed care penetration, were not found significantly more effective over time. Using small area analysis, the study indicates that improvements in socioeconomic conditions and geographic access may have helped improve the quality of primary care received by the elderly over the last decade, particularly among some minority groups.

Which Family Physicians Work Routinely With Nurse Practitioners, Physician Assistants or Certified Nurse Midwives

Facing rising numbers of insured with implementation of the Affordable Care Act, policy makers are interested in building teams of providers that can accommodate a growing demand for primary care services. Nurse Practitioners (NPs), Physician Assistants (PAs), and Certified Nurse Midwives (CNMs) already augment the physician workforce, particularly in rural areas. Our objective was to determine what physician and areal-level characteristics were associated with working with NPs, PAs or CNMs. The sample consisted of a convenience sample of physicians through the American Board of Family Medicine (ABFM) website in the fall of 2011. We linked these data to demographic and practice information collected by the ABFM and with provider information supplied from the National Provider Identifier file aggregated at the Primary Care Service Area level. Hierarchical logistic regression models were used to determine variables associated with working with NPs, PAs, or CNMs. Of the 3,855 family physicians in our sample, 60% reported routinely working with NPs, PAs, or CNMs. In regression analysis, characteristics positively associated with working with NPs, PAs, or CNMs were providing gynecological care (Odds Ratio = 1.23 [95% confidence interval, 1.06-1.42]), multispecialty group practice (OR = 1.72 [1.36-2.18]), any rural setting, and higher availability of PAs (OR = 1.40 [1.10-1.79]). Restrictive NP scope of practice laws failed to reach significance (OR = 0.86 [0.71-1.05]). This study suggests that the number of family physicians routinely working with NPs, PAs, and CNMs continues to increase, which may allow for improved access to health care, particularly in rural areas.

Multilevel modelling of Demand Responsive Transport (DRT) trips in Greater Manchester based on area-wide socio-economic data

Providing public transport in areas of low demand has long proved to be a challenge to policy makers and practitioners. With the developing economic, social and environmental trends, there is pressure for alternative solutions to the policy of subsidising conventional bus services. One potential solution is to adopt more flexible routes and/or timetables to better match the required demand. Therefore such 'on demand' or 'Demand Responsive Transport' (DRT) services (known as paratransit in the US) have been adopted in a number of locations. This paper seeks to explore the effects of area-wide factors on the demand of DRT by reporting the results of a statistical analysis of DRT service provision in the metropolitan region of Greater Manchester, the public transport authority of which offers one of the largest and most diverse range of DRT schemes in the UK. Specifically, this paper employs a multilevel modelling approach to investigate the impact of both DRT supply-oriented factors at the service area level and socio-economic factors at the lower super output area (LSOA) level on the average number of trips made by DRT per year. This hierarchical or 'nested' structure was adopted because typically the LSOAs within the same Service Area may share similar characteristics. It is found that the demand for DRT services was higher in areas with low car ownership, low population density, high pro- portion of white people, and high levels of social deprivation, measured in terms of income, employment, education, housing and services, health and disability, and living environment.

Medicare Costs and Surgeon Supply in Hospital Service Areas

To quantify the correlates of variations of Medicare per beneficiary costs at the hospital service area level and determine whether physician supply and the specialty of physicians has a significant relationship with cost variation. The American Medical Association Masterfile data on physician and surgeon location, characteristics and specialty; Census derived sociodemographic data from 2006 ZIP code level Claritas PopFacts database; and Medicare per beneficiary costs from the Dartmouth Atlas of Health Care project. A correlational analysis using bivariate plots and fixed effects linear regression models controlling for hospital service area sociodemographics and the number and characteristics of the physician supply. Data were aggregated to the Dartmouth hospital service area level from ZIP code level files. We found that costs are strongly related to the sociodemographic character of the hospital service areas and the overall supply of physicians but a mixed correlation to the specialist supply depending on the interaction of the proportion of the physician supply who are international medical graduates. The ratio of general surgeons and surgical subspecialists to population are associated with lower costs in the models, again with difference depending on the influence of international medical graduates. There is a strong association between higher costs and the local proportion of physician supply made up of graduates of non-US or Canadian medical schools and female graduates. These results suggest that strategies to reduce overall costs by changing physician supply must consider more than just overall numbers.

Socioeconomic inequality of cancer mortality in the United States: a spatial data mining approach

BackgroundThe objective of this study was to demonstrate the use of an association rule mining approach to discover associations between selected socioeconomic variables and the four most leading causes of cancer mortality in the United States. An association rule mining algorithm was applied to extract associations between the 1988–1992 cancer mortality rates for colorectal, lung, breast, and prostate cancers defined at the Health Service Area level and selected socioeconomic variables from the 1990 United States census. Geographic information system technology was used to integrate these data which were defined at different spatial resolutions, and to visualize and analyze the results from the association rule mining process.ResultsHealth Service Areas with high rates of low education, high unemployment, and low paying jobs were found to associate with higher rates of cancer mortality.ConclusionAssociation rule mining with geographic information technology helps reveal the spatial patterns of socioeconomic inequality in cancer mortality in the United States and identify regions that need further attention.