Enterprise Master Patient Index (EMPI)

The County of San Mateo Health Administration is comprised of 10 Divisions providing health and welfare across San Mateo County including (a) Administration & Central Finance, (b) Aging & Disability Services, (c) Behavioral Health & Recovery Services, (d) Correctional Health, (e) Emergency Medical Services, (f) Environmental Health, (g) Family Health, (h) Health Information Technology, (i) Public Health, Policy & Planning, (j) San Mateo Medical Center.

San Mateo County Health is seeking a next-generation Enterprise Master Person Index (EMPI) solution to modernize and strengthen its identity management capabilities across the organization. The primary objective is to replace the current system (Rhapsody) with a more advanced platform that delivers significantly higher patient matching accuracy through the use of modern techniques such as referential matching and machine learning, while also supporting contemporary interoperability standards like FHIR. A key focus is reducing the reliance on manual data stewardship by automating identity resolution processes, thereby improving operational efficiency, patient safety, and data integrity.

This initiative will also involve a comprehensive migration from the existing identity ecosystem, including the Rhapsody integration engine, to a more scalable, cloud-based, and cost-effective environment. The new solution is expected to provide seamless integration with existing clinical and administrative systems, enable real-time data exchange, and support a growing portfolio of digital health applications. Additionally, the upgraded EMPI will serve as a foundational component for enterprise analytics, population health initiatives, and coordinated care efforts by ensuring a consistent and accurate longitudinal patient record across all systems.

San Mateo County Health currently relies on the EMPI to manage approximately 765,000 patient records across multiple EMR systems, with “Golden Records” and Enterprise Unique Identifiers (EUIDs) forming the core of its patient-matching framework, supplemented by Epic’s Identity module. As part of its modernization strategy, the organization aims to move away from a legacy on-premises setup toward a more scalable, cloud-based architecture. A key priority is improving matching accuracy by incorporating referential matching or machine learning capabilities to reduce the volume of manual review required by the existing probabilistic and deterministic methods. Additionally, there is a need for more flexible, developer-friendly FHIR APIs to better support an expanding suite of digital health and patient-facing applications. Enhancing administrative efficiency is also important, particularly by making the data steward interface more intuitive for managing overlaps and merges. Ultimately, The County is seeking platform under a new contract, that will enable more advanced referential matching capabilities.