How to Understand the Master Patient Index

Understanding how an MPI works is essential to all clerical roles in the hospital. This is how they ensure that they do not create errors in the MPI database which can affect patient care and how they can view past patient admission information. The most serious errors include:

• a single patient being added multiple times resulting in multiple MRNs (known as an overlap)
• a patient being registered under another patient’s MRN, resulting in them sharing the same MRN and intermingling their health records (known as overlay) (Biddle, 2015).

Example #1 (Meditech)

Below, is a screen snip of an MPI with headings including name (will always be listed last name, first), ACCT/FIN#, Status (see below for definitions), date of visit, location of visit, and MRN.

(Alberta Health Services, 2016, pp. 10).

Status definitions:

• ADM IN: admitted inpatient
• SCH REF: scheduled referred visit
• REG: registered
• DEP ER: departed ER patient
• CLI: clinical visit (i.e. infusion clinic)
• PRE: pre-registered patient
• RCR: recurrent visit types

How to Interpret This MPI

Review the Medical Record Number (MRN) on the far-right side of the above image.

You will see that it is the same for both TEST,TRACY accounts. As you have just learned, each person is given their own unique MRN upon their first admission and they will continue to be registered under this number for every subsequent encounter. By checking the MRN number, you can ascertain that this is the same person.

Next, review the Account Number for both TEST,TRACY accounts. These will be different, as each encounter has its own unique number for billing and administrative reasons. You can tell several things from looking at the Account Number and Status. For example, TEST, TRACY’s first visit, the /15 indicates 2015 and the status indicates REG CLI means registered for a clinical visit.

Example #2 (Oracle)

Below you will find a screen snip from a different clinical information system. While it may look different, the concepts remain the same. The left side of the screen shows the patient search which was performed – this search was by name only (name Twelve Qualityconnect). The top of the screen shows the patient results which matched the search. Note that there were two matches for this name. Next review the MRN numbers listed beside each name–you will see that they are different, which indicates that there are two different patients which match that criteria. Before proceeding any further, the HUC will need to check the patient’s demographic information shown next to each (including DOB, age and address) to ascertain that they proceed with the correct patient.

In the box below, you can see all the encounters that the chosen Twelve has had with this facility. Note that beside each encounter, you should also see a specific FIN#/ACCT# for that visit, as well as other identifying information regarding the visit. The Encounter Type field provides similar information to the Status field above.

(Cerner Training, 2017, 1:39)

Alberta Health Services. (2016, July). Meditech Order Entry (OE) User Manual. 

Biddle, Matthew (2015). Maintaining the Master Patient Index: The impact of patient registration processes on data integrity. Applied Research Projects. 32.

Cerner Training. (2017, September 17). Cerner Part 2 Searching for a Patient. [Video: YouTube]

Thompson, V. D. (2018). Administrative and Clinical Procedures for the Canadian Health Professional (4th Edition). Pearson Canada.