Medical outcomes of care for breast cancer among health maintenance organization and fee-for-service patients.

The quality of medical care provided to patients with different types of health insurance coverage has only recently begun to be evaluated. Very few studies have compared the process or outcome of care for cancer. Breast cancer is a good disease to use in medical effectiveness studies because it is relatively easy to diagnose with available technology and is treated effectively if detected early. The primary objectives of this study were to compare type of treatment, stage at diagnosis, and survival for female breast cancer patients newly diagnosed through fee-for-service with third-party coverage or health maintenance organization plans offered by the same medical practice during the same time period. Using a historical cohort design, data from a tumor registry were used to compare type of treatment, stage at diagnosis, and survival for 425 patients diagnosed from 1984 through 1992; 53.6% were members of a health maintenance organization and 46.4% used a variety of fee-for-service plans. Overall, there was no difference between the two groups in type of treatment, stage at diagnosis, or survival. Using fee-for-service as the reference group, Cox regression analysis showed that the unadjusted mortality rate ratio for survival was 0.66 (95% confidence interval = 0.432-1.020), and the rate ratio adjusted for age, race, and stage was 0.80 (95% confidence interval = 0.505-1.257). It was concluded that, despite differences in the type of health insurance coverage, there do not appear to be systematic differences in medical outcomes for breast cancer among women who are treated by the same medical care provider. These findings are of interest in the context of the rapidly changing organization of medical care with its implications for clinical practice and for the quality of care offered to patients with different types of medical insurance coverage.