Background: Breast cancer missed on diagnostic mammography may contribute to delayed diagnoses, whereas false-positive results may lead to unnecessary invasive procedures. Whether accuracy of diagnostic mammography at facilities serving vulnerable women differs from other facilities is unknown.
Objective: To compare the interpretive performance of diagnostic mammography at facilities serving vulnerable women to those serving nonvulnerable women.
Design: We examined 168,251 diagnostic mammograms performed at Breast Cancer Surveillance Consortium facilities from 1999 to 2005. We used hierarchical logistic regression to compare sensitivity, false positive rates, and cancer detection rates.
Subjects: Women aged between 40 and 80 years underwent diagnostic mammography to evaluate an abnormal screening mammogram or breast problem.
Measures: Facilities were assigned vulnerability indices according to the populations served based on the proportion of mammograms performed on women with lower educational attainment, racial/ethnic minority status, limited household income, or rural residences.
Results: Sensitivity of diagnostic mammography did not vary significantly across vulnerability indices adjusted for patient-level characteristics, but false-positive rates for diagnostic mammography examinations to evaluate a breast problem were higher at facilities serving vulnerable women defined as those with lower educational attainment (odds ratio [OR], 1.39; 95% confidence interval [CI]: 1.08, 1.79); racial/ethnic minorities (OR, 1.32; 95% CI: 0.98, 1.76); limited income (OR, 1.34; 95% CI: 1.08, 1.66); and rural residence (OR, 1.55; 95% CI: 1.27, 1.88).
Conclusions: Diagnostic mammography to evaluate a breast problem at facilities serving vulnerable women had higher false positive rates than at facilities serving nonvulnerable women. This may reflect concerns that vulnerable populations may be less likely to follow-up after abnormal diagnostic mammography or concerns that such populations have higher cancer prevalence.
From the *Department of Medicine, University of California San Francisco, San Francisco, CA; †Biostatistics Unit, Group Health Research Institute, Seattle, WA; ‡Department of Biostatistics, University of Washington, Seattle, WA; and Departments of §Radiology, and ¶Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA.
Supported by the Agency for Health Care Research and Quality, grant 1 K08 HS018090–01, California Breast Cancer Research Project, grant 14IB-0062, the NIH/NCRR UCSF-CTSI grant number UL1 RR024131, and the National Cancer Institute Breast Cancer Surveillance Consortium (U01CA63740, U01CA86076, U01CA86082, U01CA63736, U01CA70013, U01CA69976, U01CA63731, U01CA70040). The collection of cancer data used in this study was supported in part by several state public health departments and cancer registries throughout the United States. The full description of these sources is available at: http://breastscreening.cancer.gov/work/acknowledgement.html.
The authors take full responsibility in the design of the study, the collection of the data, the analysis and interpretation of the data, the decision to submit the manuscript for publication, and the writing of the manuscript. The contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH.
Reprints: L. Elizabeth Goldman, MD, MCR, Department of Medicine, UCSF, 1001 Potrero Ave, Box 1364, San Francisco, CA 94110. E-mail: email@example.com.