Breast Cancer Mapping for Community Health Advocacy: Results from an Expert Panel Study

Objectives: To evaluate the utility of sub-county breast cancer mapping and articulate guidelines for its implementation by public health agencies. Methods: We convened an Expert Advisory Group (EAG) of breast cancer stakeholders from around California to elicit values, priorities, and preferred characteristics of protocols for proactive sub-county breast cancer mapping. Upon formulating a protocol, we applied it to nine years of data (2000-2008) describing invasive breast cancer in California for evaluation by the EAG. Results: Maps with sub-county resolution were seen to provide important information with a wide range of applications. Priorities included the avoidance of false positive findings, scientific credibility, and the provision of information elucidating social and environmental characteristics. A protocol utilizing Kulldorff's Scan Statistic along with post-analytic steps for refining results was elaborated; when applied to the data, four discrete regions with elevated rates of invasive breast cancer were identified and described. Conclusions: EAG priorities were readily translatable into a scientifically rigorous protocol that protected confidentiality and avoided statistically unstable rate estimates. Findings enabled participants to visualize geographically defined populations falling within and crossing county boundaries.