Breast cancer in West Islip, NY: a spatial clustering analysis with covariates.

This paper presents the results of an exploratory spatial analysis of breast cancer clustering in the community of West Islip on Long Island. Using address-level data from a survey of women in West Islip, we analyze the existence and locations of breast cancer clusters among long-term community residents. Statistical and geographical methods are used to first, estimate a logistic regression model of disease as a function of known risk factors and second, analyze spatial clustering among the cases of breast cancer not explained by the modeled risk factors. The method determines the actual locations of clusters so that if there is a potential causal factor in the environment it can be identified for further study. Although little evidence of clustering is uncovered, the methods described here have utility for exploratory spatial analysis in many health contexts.