Term: Enterprise Master Patient Index (EMPI)

Description: This is basically a higher level Master Patient Index; which is a master list of those who receive medicinal service and their demographic information. An Enterprise Master Patient Index (EMPI) is a database that contains a unique identifier for every patient in the enterprise. This would include the medical center, outpatient clinics, practice offices and rehabilitation facilities. All registration systems would look to the EMPI to obtain patient information based upon several identifiers. An EMPI will have either deterministic indexing where one can search based on an exact match of the combination of name, social security no, date of birth, and sex. The other searching mechanism is rules based via the first 4 letters of the last name, or other key identifiers.

Applications :

EMPIs have been used by various organizations. One example is the Total Access Communication Systems, which was a telephone Company. The potential of such an index is to maintain an accurate list of patient demographic information. In class, we had an example of what could be done with patient information, and found that many problems could be prevented and even detected early.

Types of patient identification problems that compromise the integrity of the EMPI typically fall into one of the following categories:
  • Duplicates: Two or more medical record numbers for one single patient.
  • Overlays: Two or more patients are assigned one record number.
  • Overlaps: Patients seen at multiple facilities have overlapping medical record numbers at each facility within an enterprise or integrated delivery network.

    Example EMPI services include:
  • Assisting clients to develop a statement of work
  • Building data and process models
  • Developing a requirements document
  • Developing a Request for Proposal (RFP) and proposal evaluation process and manual
  • Conducting analysis of proposals and providing recommendations
  • Supporting contract negotiations (for COTS or outsourced development)
  • Providing configuration, development and testing resources (for internal development option)
  • Performing IV&V during implementation

Recommended Data Elements:
Data Element
Enterprise identification number
Primary identifier used by the enterprise to identify the patient across facilities (e.g., the enterprise number or corporate number
Facility identifier
Primary identifier used by the enterprise to identify the facility contributing data to the EMPI (e.g., the facility code)
Internal patient identification
Primary identifier used by the facility to identify the patient at admission (e.g., the medical record number)
Person name
Legal name of patient or person, including surname, given name, middle name or initial, name suffixes (e.g., Junior, IV), prefixes (e.g., Father, Doctor)
Date of birth
Patient or person's date of birth. Year, month, and day of birth are entered (e.g., YYYYMMDD). It is essential that the year of birth be recorded as four numbers, not just the last two numbers
Gender of patient (e.g., male, female, unknown/not stated)
Race of patient. Race is a concept used to differentiate population groups largely on the basis of physical characteristics transmitted by descent. Races currently used by the federal government for statistical purposes are American Indian/Eskimo/Aleut, Asian or Pacific Islander, black, white, other, and unknown/not stated
Ethnicity of the patient. Ethnicity is a concept used to differentiate population groups on the basis of shared cultural characteristics or geographic origins. Ethnic designations currently used by the federal government for statistical purposes are Hispanic origin, not of Hispanic origin, and unknown
Address or location of patient’s usual residence. Components include the street address, other designation (e.g., apartment number), city, state or province, zip or postal code, country, type of address (e.g., permanent, mailing)
Alias/previous/maiden name
Any names by which the patient has been known other than the current legal name, including nicknames, maiden name, previous name that was legally changed, etc.
Social Security number
Personal identification number assigned by the US Social Security Administration
Telephone number
Telephone number at which the patient can be contacted. This may be a home or business telephone number or the telephone number of a friend, neighbor, or relative

Duplicate records and other EMPI data integrity problems impact organizations in a number of ways:
  • Quality of patient care can be compromised if a patient’s information is not readily available to caregivers. There are risks of misdiagnosis, treatment errors, and patient inconvenience or patient harm.
  • Duplication of services can occur when all records for a patient are not available. Tests and services may be repeated unnecessarily. This is costly for the facility, and risky for the patient.
  • High costs arise from duplicate tests, operational inefficiency, supplies, and rework associated with duplicate records. These costs can range from $25 to $400 per duplicate set.
  • Longitudinal records and repositories are dependent on the ability to accurately identify a patient and interface and link data correctly.
  • Operational effectiveness is affected in multiple departments. Delays in registration occur when there are multiple EMPI records for a patient. Registration staff is presented with ambiguous choices, and errors compound.
  • Privacy and confidentiality can be jeopardized unknowingly. Incorrect patient identification, especially overlays, can result in bills and other information being sent to the wrong address or the wrong insurance company.
  • Regulatory compliance with CMS billing rules and HIPAA regulations can be undermined. Duplicate records can put the facility at risk for billing errors that can lead to substantial fines for noncompliance, fraud, and abuse. Confidentiality breaches in violation of HIPAA rules can result in litigation, and significant financial penalties.

Web Resources:




Related Terminology:

Master Patient Index