OBJECTIVES: Public health approaches for prevention are considered to be successful with climbs in the numbers of services rendered.  However, more thorough evaluations are required to uncover the still unmet need that remains hidden and harder to reach. The objective of this study is to estimate the impact of physician supply, mammography facilities, and managed care penetration on use of mammography screening. METHODS: Retrospective self-reported cross-sectional data from Behavioral Risk Factor Surveillance System for years 2000, 2002, and 2004 along with county level supply variables from area resource file, were used in the analysis.  The analysis was restricted to females between 40-69 years of age.  We estimate a series of multivariate regression model to assess the effect of individual and contextual supply variables on mammography screening.  We also use variation in the physician supply, managed care penetration at the county level over the 5-year period to estimate its impact on mammography screening using a fixed effect estimation approach. RESULTS: Women living in rural areas were less likely (Coefficient=-0.023, 95% CI=-0.031-0.014) to obtain a mammogram even after controlling for supply side variable . Among the supply side variables only managed care penetration significantly predicted mammography screening.  In areas with higher managed care penetration, women were more likely to get screened. CONCLUSIONS: Insurance status was one of the major determinants of mammography screening for females residing in rural areas.  Contextual supply variables had lesser impact on mammography screening compared to individual level characteristics.