Although disparities in screening mammography have improved over the past decade, documented differences persist among women of lower socioeconomic backgrounds, the uninsured, women without a usual source of care, the elderly, recent immigrants, women in rural areas, and some racial/ethnic minorities such as NA/ANs and Hispanics. There is evidence that the actual magnitude of these disparities, particularly among low-income racial/ethnic minorities, is underestimated and that disparities persist for some subpopulations of AA/PIs and African Americans. While current population-based surveys may not accurately assess disparities in screening mammography, there are also limitations to claims-based and chart review methods of data collection. Claims-based data does not capture the experience of uninsured women, and chart reviews are subject to manual documentation errors. New methodologies are needed to more precisely determine preventive care utilization in the US, particularly within medically underserved populations.
The most significant disparities in screening mammography are based on insurance status, usual source of care, and socioeconomic status. Consequently, access-enhancing strategies, which are the most effective type of patient-targeted intervention, will continue to be important complements to programs that mediate individual change. Health care systems change, such as the implementation of a national health plan, will be vital to eliminating disparities among the uninsured and those with limited access to health care.
While meta-analyses have reported increased mammography utilization from a wide range of interventions, the overall effectiveness of such strategies may be overestimated because negative studies are less likely to be published. Although generally viewed as successful, these interventions have not reached full penetrance within all underserved communities. Continuing national and local initiatives to reach at-risk women must continue to be funded and systematically evaluated for effectiveness. We should not, however, endeavor to reach 100% utilization of screening mammography among the elderly, as a substantial number of these women will have significant comorbid illnesses that make the risks of screening outweigh the benefits. Additionally, initiatives should emphasize the importance of rescreening medically underserved women, as data indicate that more women report having been screened in the past than report recent mammogram use.10
Future research in breast cancer screening disparities is warranted in several key areas. First, more work is needed to collect accurate national screening estimates of NA/AN, AA/PI, and Hispanic subpopulations and to understand the heterogeneity within these groups that affects mammography use, such as regional variation, cultural differences, English proficiency, and sociodemographic factors. Second, there is little current data examining the long-term effectiveness of mammography-enhancing interventions. Finally, the effectiveness of different types and/or combinations of interventions in specific patient subpopulations is not well known, hampering our ability to assess cost effectiveness and make health policy decisions.
Efforts to decrease disparities in screening mammography are successful only if they result in reduced breast cancer morbidity and mortality. Despite improvements in screening rates, it is concerning that disparities in breast cancer mortality persist among underserved populations such as African Americans, Hispanics, Native Americans, Vietnamese, and Native Hawaiians.120,121
Because changes in disease outcomes lag behind public health interventions, it is possible that we have yet to witness the benefits of enhanced screening in specific underserved groups. More likely, however, screening mammography is only one of several factors impacting disparities in breast cancer mortality. Decreasing disparities in the diagnostic and cancer treatment process must also become a priority if we are to reduce mortality differentials in breast cancer.