Matchmerge Immunization Registry (MIR)

Software Partners obtained its first contract for immunization registry software with San Diego County in 1997. Input from visionary San Diego colleagues such as Dr. John Fontanesi of University of California inspired us to take a different approach from what other immunization registries were doing. Anticipating the eventual replacement of immunization registry data entry screens with provider Electronic Health Record (EHR) systems, we applied our background in data replication to create an architecture based upon linking, not merging, records from different providers for a common patient. This allows the source of each record – in this case the provider – to control his record in the immunization registry.

Similar principles governed later healthcare standards such as the Clinical Document Architecture (CDA) of Health Level Seven (HL7). Each document is “owned” by the entity that created it. It cannot be modified except by that entity; control follows responsibility for the information. The same approach is reflected in the architecture and standards governing the enterprise Master Person Index (MPI). The MPI only cross-references records from different sources belonging to the same person; it does not merge those records, and it updates them only upon receiving an update from a source system. Compared to other, older approaches to immunization registries, our approach leads to much more accurate patient records, maintaining a standard of correctness for secondary-use public health records that rises to the level expected of their originating private sector providers.

Other Immunization Registry Matchmerge Immunization Registry
“Merges” records from different providers
for the same patient.
“Links” records according to conventions of
Master Person Indexes (MPIs).
No automated “unmerge” operation exists
to undo mistakes.
Implements an automatic “unlink”
operation to undo links. “Link” relinks