Reverse geocoding: concerns about patient confidentiality in the display of geospatial health data

Abstract

Widespread availability geographic information systems (GIS) software has facilitated the use health mapping in both academia and government. Maps that display patients as points are often exchanged in public forums (journals, meetings, web). However,even these low resolution maps may reveal confidential patient location information. In this report, we describe a method to test whether privacy is being breached. We reverse geocode from maps with cases and describe the accuracy with which patient addresses can be extracted.

Figure 1

Prototypical patient map for Boston, Massachusetts. Image displays 550 randomly selected patient addresses.