Inter-Registry deduplication activities and benefits
In addition to facilitating multi-registry cohort linkages, the VPR-CLS is committed to developing a secure mechanism to support case de-duplication between U.S. cancer registries. Such an initiative is designed to improve the overall quality of cancer surveillance data. As proof of concept, pilot test linkages using hashed registry data have been performed and compared to probabilistic linkages using identifiable data. Hashed data allows registries to perform linkages on confidential data while that data is encrypted. Efforts in this area are ongoing and include modification to linkage software to support hashed, encrypted linkages and efforts of a NAACCR Task Force to establish rules for determining case ownership of inter-registry duplicates.
The long-term goal is to perform inter-registry deduplication between all U.S. central registries which would provide the following benefits:
- Reduction in the number of duplicate case reports across state lines.
- More accurate estimates of cancer incidence.
- Sharing of information on mutual cases, thereby improving the accuracy and completeness of treatment and follow-up information.
- Identification of multiple primaries where a patient is diagnose with two different primaries in two different states.
- More accurate estimates of the incidence of multiple primaries.
