When Healthcare professionals think about hospital inefficiencies typically fee for service model, inpatient services that could be handled outpatient, and unnecessary tests and procedures come to mind.   A less talked about cost is the cost of duplicates and overlays.  A duplicate occurs when a patient have two separate medical records within the same facility or in a MPI.  An overlay occurs when two separate patient’s medical records are linked into one medical record.  The average cost of each duplicate medical pair is $50 and hospitals have an average of 64,000-96,000 duplicates which amounts to $3,200,000-$4,800,000 per hospital.  The costs in patient care can be even higher due to lack of information about allergies or repeated x-rays that increase the rate of cancer.

The master patient index is the database in a healthcare organization that holds demographic and medical data for all patients of that organization and assigns them a unique identifier.  Other terms for the master patient index are enterprise master patient index, enterprise person index and corporate person index.  MPIs are used frequently in health information exchanges (HIEs); HIEs collect patient information from different hospitals and clinics and store them in one location, the MPI.  An example of an HIE is the Mass HIway, the Massachusetts statewide HIE.  Having all a patient’s clinical care data in one location improves care because all of the patient’s providers can see diagnostic tests, allergies, medicates and provider’s notes from separate facilities.  However, this only works if the master patient index can determine that the John Smith who has a primary care provider at Beth Israel Deaconess Medical Center is the same John Smith that went to Tufts Medical Center for emergency surgery.  If the Mass HIway MPI correctly links these too records then John Smith’s PCP at Beth Israel Deaconess Medical Center can access all the records from the emergency surgery John had at Tufts Medical Center.  The master patient index ID (MPIID) can be easily confused with the patient medical record number (MRN).   In the case of John, he would have 2 separate MRNs, one from Beth Israel Deaconess Medical Center and one from Tufts Medical Center and one MPIID from the Mass HIway MPI.

Going back to the cost of duplicates, you may be wondering how duplicates can create so many financial and clinical costs.  In terms of financial costs, duplicates can cause administrative inefficiencies, duplicated tests, resource drains and reimbursement losses.  For example in the case of John, if he has outstanding payments at Tufts under a different name or address and they are not correctly merged the billing department will not know to collect that fee when John comes into the hospital.  If John had a blood test on the previous medical record or at a BIDC, the provider at Tufts will redo the test which will lead to increased costs and labor.   Without a MPI John will also have to fill out a paper form with his allergies, medications and medical history at each facility, which will then have to be entered into the chart by a team member at each hospital.  Although the financial costs are large, the most important cost is the compromise in care delivery and the risk to patient safety.  When John goes to the hospital for emergency surgery at Tufts if his record is not correctly linked from BIDC and he has an allergy to penicillin, the providers at Tufts will not be aware and could administer the drug.  Duplicates can also cause a provider to repeat the same tests which put the patient at an increased risk.  Duplicate tests and procedures do not always cause harm to the patient however when x-rays, medications or invasive procedures are involved the patient could have an increased risk for adverse effects. Overlays can be a major threat to patient safety.  In the case of an overlay, if John Smith’s medical record was linked incorrectly with a Johnathan Smith who has a different blood type and John Smith needs a blood transfusion the results could be catastrophic.

Now that we know why patient matching is important we can go into how it works.  There are two different ways to combine medical record data merging and linking.  Merging occurs when there are duplicates in the same facility, if john has two medical records at BIDC, they will send an ADT message that will merge his duplicate records into one.  Linking occurs when John’s medical record at BIDC is linked with his medical record at Tufts in the Mass HIway.  The most common ways medical records are matched in the MPI are algorithms, patient smart cards and biometrics.  There are three frequently used types of algorithms in patient index matching, deterministic, rule-based and probabilistic.  Deterministic is the most simple but is the least accurate, it is based exact matches of certain data.  For example if the Mass HIway used deterministic matching and both Tufts and BIDC had John’s social security number the medical records would be automatically linked.  The most accurate type of algorithm is probabilistic, which matches a patient based on certain parameters such as first name, last name, date of birth, social security number, telephone number and address.  The algorithm calculates the likelihood that John from BIDC is the same John at Tufts by matching up the parameters in each medical record.  Rule-based algorithms are put in place to handle certain scenarios such a patients that are twins, newborns, roommates, siblings, and family members with the same name.  An example of a rule could be that all newborns cannot be automatically linked because infants are many times named “baby” as a first name which could lead to two different baby’s medical data being linked (overlays).  Biometrics and Smart cards are less widely used today, but as technology continues to evolve they will likely be implemented more often.  Smart cards are the size of credit cards and have an embedded chip that can transfer data and authenticate a patient’s identity.  Biometrics can be used to authenticate patient’s identity by scanning certain parts of the human body such as the Iris, Palm Vein or finger prints.

Duplicates and Overlays are a major cost to medical facilities and to the care of the patient.  It is important for hospitals to continuously monitor their patient indices to validate that their form of patient linking and merging is up to date and is working correctly.  If a hospital finds many duplicates or overlays they can consult their EHR vendor and a MPI consultant to help them better maintain their patient index.

Infogrpahic provided by M2SYS