Mapping between order codes and loinc result codes

Is there a mapping available that links order codes to LOINC result codes? For instance, does order code 006510 typically correspond to the following LOINC: xxx?

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Are you asking about lab order LOINCs and result LOINCs or other clinical content LOINC codes? Can you clarify?

If lab results, there are several aspects to your question.

  1. Many LOINC panel order codes do list LOINC result codes. Let’s look at a Basic Metabolic Profile LOINC LOINC 24321-2 Basic metabolic 2000 panel - Serum or Plasma
    You’ll note ther eare required results to use the order LOINC, as well as optional result LOINCs such as for the different ways a eGFR is calculated. It’s expected that the performing laboratory will choose the approrpiate LOINC for how their eGFR is reported and use that one.

  2. Highly recommend reading the LOINC User Guide if you haven’t already. There are valuable explanations of Conditional, Optional and other designations used for result LOINCs that are part of panel order LOINCs.

  3. One of the most complex is for Lupus Anticoagulant Testing. It’s been designed to follow clinical protocols as indicated in the LOINC details page. See LOINC 75881-3 Lupus anticoagulant aPTT, dRVVT and PT screening panel W Reflex You’ll note there are reflex result LOINCs included, which may or may not be performed depending on previous result values.

  4. A result LOINC may be contained in one or more order panel LOINC codes. A Hemoglobin is commonly found in a Complete Blood Count (CBC) order panel, as well as a “H&H” order panel or Hemoglobin and Hematocrit, among a whole list of other panels in LOINC 718-7 Hemoglobin [Mass/volume] in Blood (scroll down to member of these panels to see which ones.)

  5. In the US, Medicare (CMS) has defined reimbursement and billing for certain order panels like the BMP and why there are several different LOINC codes depending on if it’s the Basic Metabolic 2000 panel or the Basic Metabolic 1998 panel.

  6. That said, each performing laboratory determines the orders (tests) on their laboratory menu. They also determine in most cases which results are part of their order panels. One cannot tell the full meaning of a test by it’s name alone holds true with order panels too. One laboratory may call a test a CBC and include a Platelet Count, while another also calls their order panel a CBC, but it lacks a platelet count. These order panels would be mapped to two different LOINC codes as a result to distinguish that they are not the same order panel. Conversely one laboratory may call it’s order panel a “CBC” and another an “ABC” or automated blood count or “FBC” for full Blood count. If they are performed the same way, on the same instrument, and with the same result items in the panel, and thus mapped to the same order LOINC code, we’d know they are really the same thing, despite the different naming conventions.

  7. If you are asking about test order codes (and not LOINC codes) that each performing laboratory may use as a unique identifier to the test order on their menu, a number of reference labs will provide some of the information in their test compendium (or CLIA Specimen Collection Manual in the US). Each test order is listed in the order catalog with it’s ordering name and often given an order number that is unique. Along with the test information, many labs are providing which results are part of order panels, as well as the LOINC codes for each result. Ask the performing laboratory for their LOINC codes even if you don’t see them in the compendiums, as best practice is for them to provide.
    Some are providing the LOINC order code for their order panels. Here’s a CBC with differential example from Mayo Clinic. You’ll see the LOINC order code first, followed by the result items that are part of their CBC and their LOINCs.

  8. Are you also asking about non panel order LOINC codes such as when there is a single orderable, which is also a single resultable? The hemoglobin can be ordered singularly and resulted singularly. If so there are LOINC codes with a OrdObs indication of Both, indicating the same LOINC code can be used for when the lab test is an order and also when it is a result. Panels are order only LOINCs in OrdObs, while many result only LOINCs such as ratios or calculations of two results or interpretations have an OrdObs of Observation indicating they are usually for results only.

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