DOI: 10.3886/icpsr39579
title: Building Data Registries with Privacy and Confidentiality for Patient-Centered Outcomes Research (PCOR) [Methods Study], 2020
title: Archival Version

description: Researchers can use patient health data to compare treatments. But these data may include information, like names or social security numbers, that could identify patients. Researchers use different methods to remove such information and protect patients' privacy. Some methods work well to protect privacy but may make data less useful for research. Other methods don't protect privacy well enough.
Current methods for protecting privacy don't work well when:

The number of patients in the data set is smaller than the number of data fields, such as patient traits or health conditions, and data are updated many times
Patients' health and treatments are measured at more than one point in time
Data are displayed as a graph to better capture some types of content

In this study, the research team created three new methods. The team wanted to see if the new methods better protect patient privacy but also make sure data remain useful for research.
 To access the methods and software, please visit the AIMS Group at Emory University.
description: To develop and evaluate algorithms for building patient-centered and privacy-preserving data registries. The project had 3 specific aims: (1) develop methods for establishing registries of private data, (2) develop methods for establishing registries that contain both private and consented data, and (3) develop methods for evaluating and tracking patient privacy risks and establishing data registries that take into account fine-grained patient privacy preferences.
description: In this study, researchers designed algorithms based on the differential privacy (DP) framework to build data registries. The DP framework requires that any statistical aggregations and computations published using patient data limit or eliminate the possibility of determining if the calculations included a particular patient's record. Researchers developed three algorithms:

Distance-based sampling with adaptive threshold (DSAT) for high dimensional and dynamic data
Differentially private frequent sequence mining (PFS2) via sampling-based candidate pruning for correlated sequential data
Differentially private frequent subgraph mining (DFG) for correlated graph data where correlated data are modeled as graphs representing correlations of co-occurrences of health events
Researchers compared the performance of the new algorithms with existing algorithms.

Existing DP algorithms assume that patient data at different time points are independent or that temporal correlations do not risk re-identification of data. To quantify and control the privacy loss from existing DP algorithms for correlated sequential data, researchers developed the Control Temporal Privacy Leakage (ConTPL) method.
A nine-member stakeholder panel including patient privacy advocates, patients, privacy compliance officers, and biomedical informaticians gave input on the design and conduct of the study.
description: Datasets: 
DS1: Building Data Registries with Privacy and Confidentiality for Patient-Centered Outcomes Research (PCOR) [Methods Study], 2020