Visualizing the diffusion of digital mammography in New York state

Abstract

Background: Digital mammography saw rapid adoption during the first decade of the 2000s. We were interested in identifying the times and locations where the technology was introduced within the state of New York as a way of illustrating the uneven introduction of this technology. Methods: Using a sample of Medicare claims data from the period 2004 to 2012 from women ages 65 and over without cancer, we calculated the percentage of mammograms that were digital by zip code of residence and illustrated them with a series of smoothed maps. Results: Maps for three of the years (2005, 2008, and 2011) show the conversion from almost no digital mammography to nearly all digital mammography. The 2008 map reveals sharp disparities between areas that had and had not yet adopted the technology. Socioeconomic differences explain some of this pattern. Conclusions: Geographic disparities in access to medical technology are underappreciated relative to other sources of disparities. Our method provides a way of measuring and communicating this phenomenon. Impact: Our method could be applied to illuminate current examples, where access to medical technology is highly uneven, such as 3D tomography and robotic surgery.