Original ResearchFree Access

The Impact of Extreme Neighborhood Socioeconomic Deprivation on Access to American College of Radiology–accredited Advanced Imaging Facilities

Published Online:https://doi.org/10.1148/radiol.222182

Introduction

Neighborhood socioeconomic deprivation limits access to health care infrastructure (1). Preliminary studies indicate that some low-income and minority communities have decreased access to high-quality imaging facilities (2). American College of Radiology (ACR) facility accreditation processes are designed to ensure that patients receive safe, high-quality imaging care. There is limited nationwide data about the availability of ACR-accredited advanced imaging facilities in neighborhoods with extreme deprivation levels. Our purpose was to evaluate the effects of extreme neighborhood deprivation on access to ACR-accredited advanced imaging facilities.

Materials and Methods

Institutional review board approval was not necessary for this retrospective cross-sectional study that used Health Insurance Portability and Accountability Act–compliant publicly available data. The primary exposure was extreme socioeconomic disadvantage measured by the Area Deprivation Index, which uses 17 U.S. Census–based metrics to derive socioeconomic disadvantage percentiles for U.S. zip codes (1). Zip codes with greater than or equal to 97th percentile of Area Deprivation Index scores were considered extremely disadvantaged, and zip codes less than or equal to third percentile of Area Deprivation Index scores were considered extremely advantaged. The remaining 94% of zip codes were excluded from this analysis. Primary outcomes included the availability (yes or no) of ACR-accredited advanced imaging facilities (3). The χ2 tests evaluated the association between access and deprivation, stratified by rural status, and defined by rural-urban commuting area codes (4). Sample sizes were based on convenience. Two-tailed P values less than .05 were considered to indicate statistical significance. Analyses were conducted by using statistical software (Stata 17.0; StataCorp).

Results

Among 41 683 U.S. zip codes, 2796 met the criteria for extremely disadvantaged (1160 rural, 1636 urban), and 1028 met the criteria for extremely advantaged (39 rural, 989 urban). A higher proportion of rural zip codes was extremely disadvantaged (41% vs 4%; P < .001). Extremely disadvantaged zip codes were less likely to have access to ACR-accredited facilities with CT (21% vs 32%), MRI (19% vs 32%), nuclear medicine (11% vs 18%), PET (7% vs 13%), US (14% vs 29%), lung cancer screening centers of excellence (5% vs 12%), diagnostic centers of excellence (1% vs 4%), and radiation oncology (3% vs 8%) (all P < .001) (Fig 1). In urban areas, extremely disadvantaged zip codes were less likely to have access to facilities with nuclear medicine (15% vs 19%; P = .007), PET (9% vs 13%; P = .003), radiation oncology (5% vs 8%; P = .001), CT (26% vs 33%; P < .001), MRI (25% vs 33%; P < .001), US (20% vs 30%; P < .001), lung cancer screening centers of excellence (7% vs 13%; P < .001), and diagnostic centers of excellence (2% vs 4%; P < .001) (Fig 2). Analyses for rural areas were limited by small numbers of extremely advantaged zip codes.

Bar graph shows the percentage of extremely advantaged and extremely                     disadvantaged zip codes with American College of Radiology                     (ACR)–accredited advanced imaging facilities. Socioeconomic disadvantage                     at the zip code level was measured by the Area Deprivation Index. Zip codes at                     greater than or equal to 97th percentile of Area Deprivation Index scores were                     considered extremely disadvantaged, zip codes at less than or equal to third                     percentile of Area Deprivation Index scores were considered extremely                     advantaged, and the remaining 94% of zip codes were excluded from this analysis.                     COE = centers of excellence.

Figure 1: Bar graph shows the percentage of extremely advantaged and extremely disadvantaged zip codes with American College of Radiology (ACR)–accredited advanced imaging facilities. Socioeconomic disadvantage at the zip code level was measured by the Area Deprivation Index. Zip codes at greater than or equal to 97th percentile of Area Deprivation Index scores were considered extremely disadvantaged, zip codes at less than or equal to third percentile of Area Deprivation Index scores were considered extremely advantaged, and the remaining 94% of zip codes were excluded from this analysis. COE = centers of excellence.

Bar graph shows the percentage of extremely advantaged and extremely                     disadvantaged zip codes with American College of Radiology                     (ACR)–accredited advanced imaging facilities in urban areas.                     Socioeconomic disadvantage at the zip code level was measured by the Area                     Deprivation Index. Zip codes at greater than or equal to 97th percentile of Area                     Deprivation Index scores were considered extremely disadvantaged, zip codes at                     less than or equal to third percentile of Area Deprivation Index scores were                     considered extremely advantaged, and the remaining 94% of zip codes were                     excluded from this analysis. Rural-urban commuting area codes were used to                     define urban status with rural-urban commuting codes less than 4 considered to                     be urban. COE = centers of excellence.

Figure 2: Bar graph shows the percentage of extremely advantaged and extremely disadvantaged zip codes with American College of Radiology (ACR)–accredited advanced imaging facilities in urban areas. Socioeconomic disadvantage at the zip code level was measured by the Area Deprivation Index. Zip codes at greater than or equal to 97th percentile of Area Deprivation Index scores were considered extremely disadvantaged, zip codes at less than or equal to third percentile of Area Deprivation Index scores were considered extremely advantaged, and the remaining 94% of zip codes were excluded from this analysis. Rural-urban commuting area codes were used to define urban status with rural-urban commuting codes less than 4 considered to be urban. COE = centers of excellence.

Discussion

U.S. zip codes with extreme levels of socioeconomic disadvantage were less likely to have ACR-accredited facilities and centers of excellence. Decreased geographic access to high-quality imaging facilities may lead to delayed or missed diagnoses, potentially exacerbating health disparities (2). Potential limitations of our study included ACR accreditation as a measure of imaging quality because high-quality facilities located in areas of extreme deprivation may be unable to afford accreditation fees. Additionally, we did not identify specific components of the Area Deprivation Index associated with the presence of advanced imaging facilities. Conclusions related to specific imaging facility zip codes may not be generalizable because these zip codes may be adequately served by facilities from surrounding zip codes. Our study focused exclusively on zip codes that were extremely disadvantaged and extremely advantaged, limiting conclusions about the entire range of U.S. zip codes. Prior studies (5) have suggested that extremely deprived zip codes drive inequitable health outcomes. Prioritizing expansion of imaging facilities in areas with extreme deprivation may be required to reduce disparities in conjunction with comprehensive efforts to address social determinants of health. Future studies should evaluate the extent to which improving geographic access can mitigate documented socioeconomic barriers experienced by diverse patient populations (6).

Disclosures of conflicts of interest: O.J. No relevant relationships. E.M.S. No relevant relationships. R.C.M. Grant from GE-GERRAF; consulting fees from Hologic; payment or honoraria for lectures from GE Healthcare. V.L.M. Grant from Pfizer. N.J.R. No relevant relationships. A.S.B.W. No relevant relationships. I.A.W. Support for meeting attendance from Wisconsin Radiological Society; president, Wisconsin Radiological Society; chair, ACR PFCC; Outreach Committee chair, American College of Radiology; GSER VA committee. E.J.F. NCI Research Diversity supplement, ACR Innovation Grant, MGH Physician Scientist Development Award, NAM Scholars in Diagnostic Excellence grant recipient; payment from WebMD/Medscape and grand rounds speaker honoraria; support for attending meetings from the National Lung Cancer Roundtable Summit; co-chair, RSNA Health Equity Committee; JACR associate editor of Health Equity. A.M. No relevant relationships. A.K.N. No relevant relationships.

Author Contributions

Author contributions: Guarantors of integrity of entire study, R.C.M., A.S.B.W., A.K.N.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; approval of final version of submitted manuscript, all authors; agrees to ensure any questions related to the work are appropriately resolved, all authors; literature research, O.J., R.C.M., V.L.M., A.S.B.W., E.J.F., A.M., A.K.N.; clinical studies, R.C.M., V.L.M., N.J.R., I.A.W., A.K.N.; experimental studies, R.C.M., A.K.N.; statistical analysis, R.C.M., V.L.M., N.J.R., A.M., A.K.N.; and manuscript editing, O.J., E.M.S., R.C.M., V.L.M., N.J.R., E.J.F., A.M., A.K.N.

V.L.M. supported by a grant from the P30 Cancer Center (P30CA008748).

References

Article History

Received: Aug 29 2022
Revision requested: Nov 1 2022
Revision received: Dec 8 2022
Accepted: Jan 27 2023
Published online: Mar 14 2023