To our knowledge this is the first time-to-event analysis with before-after comparisons to examine associations between implementation of case management and free treatment for BCCEDP participants, and diagnostic and treatment delays. In this empirical evaluation of Massachusetts BCCEDP data, we found that implementation of case management was associated with improved timely diagnostic resolution following an abnormal mammogram. Notably, the association between case management and diagnostic delay did not differ by race or ethnicity. Case management was not associated with changes in time to treatment in our study. We also found no association between the implementation of free treatment and delays in diagnosis or treatment beyond improvements associated with case management.
Our finding that case management improved time to diagnosis is consistent with evidence from smaller observational studies and randomized trials that demonstrated patient navigation services successfully improved timely diagnosis for low income, minority women.9-14
Randomized trials found that women who received patient navigation experienced a lower mean time to diagnostic resolution relative to those who received usual care (25 days vs. 43 days)12
, and were more likely to receive a timely diagnosis (77% vs. 57%).11
We attribute similarities between our findings and earlier research to comparable activities performed by the Massachusetts BCCEDP case managers and patient navigators. These services likely removed barriers to diagnosis through psychosocial support and navigation of the health system. Unfortunately, we are not able to compare the level of delay or change in delay in our study to earlier research due to differences in criteria for inclusion of BI-RADS categories, definitions of timely follow-up, methods for censoring missing events, and choice of statistics.
We found only one study of patient navigation that examined time to treatment.11
This trial showed a greater percentage of the patient navigation group initiated treatment within 90 days of an abnormal mammogram (80%, n = 5), compared to usual care (50%, n = 10).11
The low number of women diagnosed with breast cancer precluded statistical testing of this difference. We experienced similar power issues in our adjusted analysis of treatment delay. With approximately 550 women in the pre-case management and post-case management periods, we had only 45% power to detect the 10% change in treatment delay, at an alpha-level of 0.05. However, when testing for unadjusted trends across all three study periods, we found a significant decrease in treatment delay.
The free treatment policy was not associated with timeliness of diagnostic resolution or initiation of treatment, beyond improvements observed after implementation of case management. We attribute this finding to two factors. First, barriers to timely resolution of an abnormal mammogram are primarily due to health system factors,20-24
and patient factors20-22
that were addressed through case management. Second, given the size of our sample, the probability of a false-negative finding was high at an alpha-level of 0.05. We had only 22% power to detect the 3% change in diagnostic delay, and 10% power to detect the 3% change in treatment delay following implementation of free treatment. Moreover, the greatest benefits of free treatment may be found in outcomes not measured in this study, such as improved receipt of treatment sessions, reduced anxiety, and mitigation of the financial burden of cancer treatment.3
The greater RR of diagnostic delay among Asian women should be interpreted carefully, as this estimate is strongly influenced by outlier values for time to resolution. Median days to diagnosis, a measure insensitive to outliers, showed that 50% of Asian women received diagnostic resolution within the same number of days as White women, 30 days versus 29 days, respectively. We found no other associations by race/ethnicity, and the relationship between case management and relative risk of diagnostic delay did not differ by race or ethnicity. This result implies that policies enacted to address barriers to care for low-income women, in addition to providing coverage for services, may improve the quality of care for all women served.
The observed lower risk of diagnostic delay among women with an abnormal CBE and among women with an index diagnostic mammogram are consistent with earlier research that suggests women with the greatest clinical need receive more timely follow-up.25
The observed association between mammogram use and treatment delay is similar to an earlier study that found women who completed previous mammograms had longer time from abnormal mammogram to initiation of treatment.26
Research is needed to inform our understanding of how earlier experiences with mammography may influence timely follow-up for subsequent tests.
Our ability to describe client participation in the Massachusetts BCCEDP case management and free treatment was limited by lack of data on the type and frequency of services provided to women. More detailed information on program participation is kept in local records by contractors but is not summarized in a data source at the Massachusetts BCCEDP. Our study also did not have measures for history of breast cancer, use of hormone replacement therapy, or prior screening outside the program, which may have influenced timely follow-up if these characteristics changed over time. However, we did control for patient and clinical characteristics most likely to be associated with diagnostic and treatment delays, to account for temporal changes in the race/ethnicity, education level, primary language, type of index mammogram, breast symptoms, and prior mammogram use of program participants. Temporal change in activities not related to the program under study but associated with the outcome is of greatest concern in before-after intervention studies that lack a comparison group. However, we are not aware of broader regional or statewide initiatives to improve follow-up of abnormal mammograms during the period when case management was implemented.
Several studies have demonstrated improved time to diagnostic resolution following implementation of patient navigation. However, gaps remain in knowledge on why this service is effective and whether the benefits outweigh the cost of maintaining the service. Future research can assess more detailed information on the costs and types of services and interactions between patients and navigators. Also, measuring more proximal outcomes of patient navigation may guide our ability to design effective programs by determining whether greater satisfaction with care or reduced anxiety over abnormal test results12, 16
improves timely follow-up.
Our analysis was limited to one potential outcome of the free treatment policy. A more comprehensive evaluation is needed to examine the impact of free treatment on out-of-pocket costs and standards of care given that income level, insurance status, and race are associated with these factors. Out-of-pocket costs for cancer care can force patients to incur debt, even when they are covered by private insurance.27
In addition, standards of care for breast cancer are less likely to be followed for women who reside in impoverished areas, are uninsured, enrolled in Medicaid, or of black race.5, 28-32
The rate of timely follow-up after abnormal mammograms in this study was within the range reported in other studies. Earlier reports of diagnostic delays greater than 60 days have ranged from 18%-29% (Massachusetts BCCEDP 20%), and treatment delays greater than 90 days ranged from 5% - 22% (Massachusetts BCCEDP 11%).26, 33-35
Results from our study may not be generalizable to other BCCEDP programs because the structure and implementation of case management services varies across sites. Nonetheless, our methods could readily be applied by other investigators to guide policy makers about the impact of BCCEDP programs in other states.
While improvement in rates of successful follow-up after abnormal findings are impressive for this public program, a reduction in disparities will also require a shift in social determinants of disease burden.36
All women need insurance coverage for breast cancer screening and diagnostic services, particularly low-income women who are not able to pay for medical services out-of-pocket. However, limited funding for the BCCEDP means that services reach approximately 13% of eligible women37
, and breast cancer screening remains inaccessible for many low-income women.
Our study demonstrated that most women who participated in the Massachusetts BCCEDP received follow-up after an abnormal mammogram within the time recommended by clinical guidelines. Implementation of a case management policy through the Massachusetts BCCEDP was associated with improved time to resolution following an abnormal mammogram and the benefits of this policy did not differ by race/ethnicity.