How SNOMED-CT fits into the ICD-10 transition

Carl Natale
by Carl Natale

While we're debating a new ICD-10 deadline, let's take a break to revisit SNOMED-CT.

Mostly because the delay renews the ICD-11 advocates, and ICD-11 is supposed to be based on SNOMED-CT.

What is SNOMED-CT?

First let's understand SNOMED-CT.

  • The Systematized Nomenclature of Medicine — Clinical Terms (SNOMED-CT)  is a medical terminology created by the College of American Pathologists (CAP).
  • SNOMED-CT is a terminology designed for input into electronic health records (EHRs).
  • SNOMED-CT is not a flat list of numbers and corresponding terms. It's a database.
  • The SNOMED-CT database is a complex relationship of concepts. The 96-page User Guide explains how it's organized.

Why not use SNOMED-CT instead of ICD-10 coding?

SNOMED-CT is a terminology designed for input into EHRs. The terms are too granular to be used for reporting. ICD-10 is a classification designed for output or reports. Each ICD code aggregates the details input into the medical records.

You can criticize ICD-10-CM/PCS for not having enough specificity, but that's kind of a feature not a glitch. A report based upon SNOMED-CT would simply be a copy of the medical records themselves. There must be some sort of grouping, classification and simplification of data to be useful.

Also, SNOMED-CT is designed to be managed by computer. It's not just a flat list of numbers and corresponding terms. It's a complex relationship of concepts.

It is very appropriate to talk about how physicians can use SNOMED-CT to enter data. It just doesn't go far enough.

The thing is, when physicians understand the classification system, they understand what's important to the reimbursers and researchers. They can use that knowledge to make sure they capture the right data. Then they're doing more than treating a patient. They're helping others understand disease and treatment.

Physicians are going to use SNOMED to communicate with EHRs  to comply with Meaningful Use. So the transition to SNOMED-CT already is in the works.

But all that data collected using SNOMED-CT will need to be reported in a classification system. ICD-10 codes will be mandated because they classify more diseases, injuries, factors and procedures than the ICD-9 codes. And someday ICD-11 codes will be required to take advantage of the next level of classification.

SNOMED should make it easier to document to the required specificity. The EHR system should convert that data to ICD information. Ideally, the physicians won't know what revision of ICD is being used. They should just need to know what needs to be recorded.