SNOMED CT vs ICD-10

A. 

Since SNOMED CT is a clinical terminology, it is inherently more appropriate for clinical documentation of diagnoses in an EHR than other terminologies or classifications, such as ICD-9. SNOMED CT is not necessarily superior to ICD-9 or 10; they were created for different reasons. Using a standard medical terminology to capture and store diagnosis (and other medical terms) in an EHR ensures consistent expression of similar concepts which can be leveraged for decision support, reporting, and analytics, while ensuring consistent communication across the healthcare community — all of which leads to better care.

Due to its use in medical billing, ICD is largely familiar to healthcare providers and was incorporated into many EHRs as a way to capture diagnoses. The primary limitation with this strategy is the lack of clinical coverage available in ICD-9, which contains approximately 14,000 unique concepts.

SNOMED CT, on the other hand, has more than 100,000 unique concepts and many more synonyms and abbreviations. This also far exceeds the 68,000 codes in ICD-10, many of which are not unique at the diagnosis level, such as two codes to express a left ankle fracture versus a right ankle fracture. The diagnosis of “metabolic acidosis” is an example that demonstrates this lack of diagnostic specificity. In SNOMED CT, it is expressed as “metabolic acidosis” (code 5945509) as opposed to simply “Adicosis” in ICD-9 (code 276.2) or ICD-10 (code E87.2). Obviously, from a clinical perspective, it is important to make the distinction between other types of acidoses, such as respiratory or lactic, which is only possible using SNOMED CT. 

From source: https://www.practicefusion.com/blog/transitioning-snomed-ct-diagnoses/

B.

The SNOMED vocabulary encompasses more than 340,000 concepts, 794,000 descriptions, 19 hierarchies, and 920,000 relationships, drilling deep into diseases and their interrelationships. The scope of SNOMED CT covers topical areas such as problems, diagnosis, organisms, pharmaceutical descriptions, and anatomic areas, enabling clinicians to capture, store, display, and query clinical detail in EHRs. 

In contrast, ICD-10 serves a different purpose as a disease classification system for reporting and billing. 

There are more than 15000 LOINC terms linked to SNOMED CT .

When clinical terms are mapped between ICD-9, ICD-10, and SNOMED CT, healthcare organizations can seamlessly achieve greater revenue cycle efficiencies and accuracies by eliminating productivity losses associated with trying to identify the correct code from ICD-10’s expansive 155,000 options.

Consider the complexities of the following example:

A digital myxoid cyst (sometimes called a mucous cyst) refers to a benign swelling that occurs on the fingers or, sometimes, the toes. For the most part, in ICD-10, this condition is coded under M71.349—Other bursal cyst, unspecified hand. In SNOMED CT, it falls under 404098005—Digital mucous cyst.

Providers typically search for this condition by referencing it as a “myxoid cyst,” yet ICD-10 does not recognize that terminology. In ICD-10, a digital myxoid cyst is categorized the following way:

• Parent: M71.34, Other Bursal Cyst, Hand
• Siblings: M71.341, Other Bursal Cyst, Right, M71.342, Other Bursal Cyst, Left Hand
• Diagnostic Category: 08
• Chronic Condition Indicator: No
• Billable: Yes

In contrast, the SNOMED CT classification of myxoid cyst will appear as follows:

• Has Parents: 248519003 Lump on Extremities (Finding); 128597007 Disorder of Digit (Disorder); 445008009 Ganglion Cyst (Disorder)
• Has an Associated Morphology: 71307009 Ganglion Cyst (Morphologic Abnormality)
• Has a Finding Site: Digit Structure (Body Structure)
• Is A: 445008009 Ganglion Cyst (Disorder)
• Is A: 248519003 Lump on Extremities (Finding)
• Is A: 128597007 Disorder of Digit (Disorder)
• Synonyms: Digital Myxoid Cyst, Digital Synovial Cyst, Digital Mucous Cyst

The advantage of SNOMED CT in this case is that clinicians can query using common language (Digital myxoid cyst). Once a clinician has selected the SNOMED concept of digital mucous cyst, the EHR should prompt them to select the correct billing code from the ICD-10 hierarchy that describes all options for other bursal cyst, hand. This ICD-10 term is then added to the diagnosis list and sent to HIM for verification. Without SNOMED CT and associated maps to ICD-10-CM, the clinician would need to search for the ICD-10 term “bursal cyst”—a term that does not adequately describe most patients’ conditions and is not language that is natural to a clinician.

While the good news is that SNOMED CT is now widely used, the industry at large recognizes that adoption of the standard must continue. In its recent report, “Optimizing Strategies for Clinical Decision Support, Summary of Meeting Series,” the National Academy of Medicine makes several recommendations for a national strategy on standardizing clinical decision support systems.6 One of the challenges noted in this report is data quality and use of standards in clinical data. SNOMED CT is the recognized standard for recording this data in a codified manner. Going forward, HIM professionals will play a critical role in the continued adoption and advancement of this very important clinical vocabulary.

More information on SNOMED CT can be found at the following links:

• US National Library of Medicine: www.nlm.nih.gov/healthit/snomedct/index.html
• SNOMED International—General information as well as a link to the E-learning Center: www.snomed.org/snomed-ct; take the SNOMED CT Foundation Course before undertaking the more advanced courses: www.snomed.org/snomed-ct/learn-more/snomed-ct-elearning-courses

Notes

1. SNOMED International. “SNOMED CT: The Global Language of Healthcare.” www.snomed.org/snomed-ct.
2. Ibid.
3. SNOMED International. “What is SNOMED CT?” www.snomed.org/snomed-ct/what-is-snomed-ct.
4. Indiana University School of Medicine. “New Regenstrief and IHTSDO agreement to make EMRs more effective at improving health care.” Press release. January, 24 2013. http://news.medicine.iu.edu/releases/2013/07/ihtsdo-loinc.shtml.
5. SNOMED International. “LOINC.” www.snomed.org/snomed-ct/mapping-to-other-terminologies/loinc.
6. National Academy of Medicine. “Optimizing Strategies for Clinical Decision Support: Summary of a Meeting Series.” 2017. https://nam.edu/wp-content/uploads/2017/11/Optimizing-Strategies-for-Clinical-Decision-Support.pdf.

Ref https://bok.ahima.org/doc?oid=302574