Launch of Automated Privacy Preserving Record Linkage (PPRL) Methodology for VPR Studies

On April 2, 2026, the first Virtual Pooled Registry (VPR) Privacy Preserving Record Linkage (PPRL) was initiated between the U.S. Radiologic Technologist Study (USRT) and the 47 VPR registries. For some registries, this linkage was performed automatically by IMS, thereby minimizing the impact on registry resources. The remaining registries performed the PPRL linkage internally. Additional background on the PPRL process can be found in the Narrative article, Privacy Preserving Record Linkage: Coming Soon to the Virtual Pooled Registry.

At the time of the USRT linkage, 27 of the 47 VPR registries had a fully executed agreement to allow IMS to perform the linkage on their behalf and had submitted their hashed registry file for inclusion in the automated linkage process. For these registries, once the hashed study file was ready, IMS launched an automated, scripted process to link the researchers hashed file with the hashed registry files and then upload the resulting match count report to the VPR.

The automated linkage process took just over 105 minutes to run consecutive linkages between the hashed study file (N=146,022) and the 27 individual registry files. Processing times per registry ranged from 43 seconds to 18 minutes, 37 seconds. Only one other registry file took more than 15 minutes to process, with 20 registries taking less than 4 minutes.

Once the automated linkage was completed, the remaining 20 VPR registries were then prompted to download the hashed study file, run the study linkage in-house against their hashed registry file, and upload their resulting match count report to the VPR. Eighty-five percent of these registries uploaded their match reports within 15 days of being notified that the study file was available for linkage.

In the coming months, additional PPRL linkages will be performed for new studies and relinkages with the Sister Study, Women’s Health Initiative, Black Women’s Health Study, NYU Women’s Health Study, and the Atherosclerosis Risk in Communities (ARIC) Study. Results from completed linkages will be shared at the upcoming NAACCR Virtual Conference.