Enterprise Master Person Index (EMPI)

The Department of Social Services (DSS) is responsible for Health Information Technology (Health IT), including Health Information Exchange (HIE) for the State’s Medicaid population. The DSS has made steady progress on implementing its roadmap for Health IT and HIE in Connecticut focusing on Medicaid beneficiaries. The DSS has aligned its strategic Health IT vision and goals with those of the Office of the National Coordinator for Health Information Technology (ONC) and the Centers for Medicare and Medicaid Services (CMS) by adopting a vision anchored in providing an integrated person-centered system facilitating, efficient and evidence-based health care delivery for all Connecticut residents.

In the long-term, the EMPI will serve as an authoritative source of person information.

EMPI assists in patient/person identification issues, and promotes the exchange of accurate information across the healthcare ecosystem.  Essentially, EMPI serves as an enterprise solution across a healthcare organization to maintain consistent, accurate and current demographic data on people. Each person is assigned a unique identifier that is used to refer to him or her across enterprises. The main objective is to ensure that each person is represented only once across all these systems.


2018 LeanCT Showcase

Thumbnail image of Lean Poster.  EMPI Brochure
 Leading Through Change Poster
 EMPI Brochure


The DSS implemented the EMPI in April 2014 with a goal of creating a consolidated view of patient/person information across disparate source systems as well as workflow and basic reporting tools for ongoing maintenance of the system.  To-date the EMPI has been used by the state’s eligibility and enrollment system (ImpaCT) and the state’s Health Insurance Exchange (HIX) system Access Health Connecticut (AhCT). EMPI is hosted by the State’s Bureau of Enterprise Systems and Technology (BEST).

Future phases include integration with the Medicaid HIE initiatives and to promote the system as a statewide enterprise asset that has the potential to serve both public and private state Medicaid partners to onboard as subscribing systems. Preliminary discussions have occurred with DSS sister agencies within the Department of Children and Families (DCF) and the Department of Developmental Services (DDS).  Traditionally, these agencies have operated independently and made health IT decisions autonomously. Interoperability within and across agencies will support the exchange and use of information to coordinate services and inform decision making.



Contributing System

June 2017

October 2017

January 2018

 April 2018

Dept. of Social Services



3,079,138 3,099,635

Insurance Exchange



1,684,210 1,711,135


Enterprise Unique IDs



3,214,654 3,236,315