Why we like lab categories, and how you can get them for free

by Jim Shalaby

Here we are, a company focused on semantics and interoperability, proclaiming our support for admittedly somewhat arbitrary lab categories... Given a thousand distinct lab results, how likely is it that individual clinicians would group them into the same categories (such as ‘chemistry tests’, ‘hematology tests’, etc)? On the flip side, given a handful of categories, how likely is it that any of us could accurately predict each of the hundreds of lab results that have been rolled up into those buckets? And yet, we like lab categories. What’s up with that?

There is a lot of talk lately about clinician burden, with a lot of folks (such as ONC/CMS, AAFP, HL7) looking into ways of easing that burden. We’ve previously talked about custom views as one technique to ease clinician burden. And just as sections provide a useful navigational paradigm for clinical documents, we believe that lab categories provide similar functionality that can facilitate order entry and results reviewing.

We spent some time looking over LOINC® categories, and, while not ‘standardized’ per se, have found them to be intuitive. We took a look at the ‘LOINC 2000’ (the 2000 most common LOINC codes), examining how they are classified into the LOINC Multiaxial hierarchy, and how they are grouped into classes. LOINC assigns each code to a general category called a Class. LOINC classes are relatively broad and are intended to make it easier to sort and browse. They are not intended to be binding definitional characteristics of the term. Classes such as ‘Microbiology’, ‘Serology’, ‘Molecular Pathology’, ‘Blood Bank’, ‘Chemistry’, and ‘Hematology’, while not definitional, are commonly known to clinicians.

We’d like to share with you what we came up with. Our ‘Elimu LOINC2000 with Categories’ download is a subset of the full LOINC database that includes the class of each LOINC2000 test, enhanced with the class description. The top 15 classes in the list are:

  • Chemistry

  • Microbiology

  • Hematology

  • Drug levels & Toxicology

  • Response to antigens

  • Urinalysis

  • Coagulation study

  • Serology

  • Antibiotic susceptibilities

  • Specimen characteristics

  • Blood bank

  • Cell surface models

  • Fertility

  • Cytology

  • Gene mutation

We have a number of clients who leverage these categories - their local codes are mapped to LOINC, and then the LOINC categories are used to ease order entry and/or results reviewing in the EHR. Our thanks go to LOINC® for providing this clinician-friendly enhancement to the LOINC database.