Review Article

Ensuring Confidentiality of Geocoded Health Data: Assessing Geographic Masking Strategies for Individual-Level Data

Figure 4

Conceptual illustration of geographic masking. A set of original locations (a) is created using address geocoding or field data collection using GPS. These locations correspond very closely to the residences of interest, although a certain amount of error might be present. For each location, a masked representation is created (b) by displacing the original location using one of several algorithms. Most algorithms include a certain degree of randomness in the displacement. The original locations are removed from the dataset, resulting in a set of masked locations (c) for publication and distribution purposes. The set of masked locations has the same number of observations as the set of original locations.
567049.fig.004a
(a) Original locations
567049.fig.004b
(b) Original + masked locations
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(c) Masked locations