Information Systems
Are you hearing about LOINC® and wondering what it is? You're not alone. As stages 2 and 3 for Meaningful Use become reality, you will be hearing even more about it.
LOINC (Logical Observation Identifiers Names and Codes) was initiated in 1994 by the Regenstrief Institute, Indianapolis, and the LOINC committee.1 The LOINC database provides a universal code system for identifying laboratory and clinical test results. These codes are used in electronic messages such as Health Level Seven (HL7), so that when hospitals, physicians, health maintenance organizations, health information exchanges, researchers and public health departments receive such messages from multiple sources, they can automatically file the results in the right slots of their medical records, research and/or public health systems. LOINC facilitates the exchange and pooling of results, such as blood hemoglobin, serum potassium or vital signs for clinical care, outcomes management and research.
Most laboratories identify tests in HL7 messages by means of their internal (and idiosyncratic) code values. Receiving medical informatics systems cannot fully "understand" the results they receive unless they either adopt the producer's laboratory codes (which is impossible if the informatics system receives results from multiple source laboratories, e.g., the hospital lab, physician office lab and local commercial lab), or invest in the work to map each laboratory's coding system to their internal code system.
Because there are over 58,000 entries in the database, the Regenstrief Institute has also developed RELMA® (the Regenstrief LOINC Mapping Assistant), a tool that can be downloaded or used online to support browsing and search of the LOINC database to help you map your local test codes to LOINC. Both LOINC and RELMA and their help manuals are available for free at www.loinc.org. Users cannot modify official codes but can modify the table to extend them locally or for their own use.2
Why We Need LOINC
If you intend to demonstrate Meaningful Use and receive the incentive payments, you will need to be familiar with LOINC. The standards, implementation guides and criteria such as LOINC to be used for certification are included in the HHS/Office of the National Coordinator for Health Information Technology (ONC) final rule.3
Test procedures to evaluate conformance of EHR technology to ONC's requirements are defined by the National Institute of Standards and Technology (NIST). The NIST "Test Procedure for §170.302 (h) Incorporate Laboratory Test Results" contains the following test data elements:4
• Test Result
• Test Report Date
• Test Type
• LOINC Code
• Test Name (and Normal Range)
• Test Result Value
• Test Result Unit of Measure
• Test Specimen Source
• Condition/Disposition of Specimen
EHR vendors need to receive LOINC if they want to be certified. Currently, for Stage 1 they just need to demonstrate they can receive the code. Stages 2 and 3 for Meaningful Use will focus more on interoperability so more vendors will be requiring the codes from the LIS. It is the responsibility of the EHR to translate the codes into their human readable form.
Understanding, Using LOINC Database
The overall organization of the database is divided first into four categories-lab, clinical, attachments and surveys. (This split is recorded in CLASSTYPE.) The laboratory portion is further divided into the usual categories of chemistry, hematology, serology, microbiology (which includes parasitology and virology) and toxicology. Antibiotic susceptibilities have their own category.
Each LOINC record (fully specified name) corresponds to a single test result by method or panel. While each LOINC is unique, the codes were not designed nor intended to be unique by testing location. For example, your lab may use the same methodology as your reference lab. If so, both results would use the same LOINC. Each database record includes six fields for the unique specification of each identified single test, observation or measurement. For example:
The analyte is sodium, measured by substance concentration, done at one point in time, on either serum or plasma, and the result is quantitative. In this case, the method used is not included.
Populating Your LIS With LOINC
Now that you know all about LOINC, the million dollar question becomes: "How do I get this information in my LIS?" It would be great if your LIS vendor could do this for you; however, they simply can not. The reality is that there are far too many variables in each of your test menu dictionaries.
Consider the simple test, glucose. Your analyzer may contain only one method for glucose, but how many variations of glucose do you use at your facility? Is it serum, urine, CSF or another fluid? Is it fasting, timed, following an oral challenge, and if so, how many hours? Do you use reagents manufactured by the instrument vendor or are you using another vendor's reagents?
The method may vary between the instrument vendor's and the third party reagents. Each of these variations has its own LOINC. Multiply that by the number of clients for each LIS vendor and it becomes an impossible task to simply import the codes. A search of the LOINC database for glucose brings up 851 different codes. How would your LIS vendor possibly know which one to map to yours? The appropriate code depends on the combination of the instrument and reagent vendors.
There are ways to minimize the scope of entering the codes in your LIS. Call your instrument and/or reagent vendor(s) and ask them what LOINC is appropriate for the method used on your analyzer. Also understand that the method on one analyzer in a series may differ from the next generation of that analyzer from the same manufacturer. Some vendors are beginning to include the LOINC codes in their package inserts. Once the codes are populated into the correct field of the LIS, they will be included in the interface transmission to the EMR.
Ginger Wooster is the director of Regulatory Affairs and application specialist for Orchard Software.
References
1. http://www.regenstrief.org/.
2. www.search.loinc.org
3. 45 CFR Part 170 Health Information Technology: Initial Set of Standards, Implementation Specifications, and Certification Criteria for Electronic Health Record Technology; Final Rule: page 44599
4. www.nist.gov