HPO to SNOMED mapping - the objectives
- The objectives was to produce a mapping to a fully logically defined SNOMED target, so that if a direct map to a SNOMED concept was not available, an expression was constructed using Compositional Grammar and post-coordination. The map produced would then be used during configuration of healthcare systems or in an expression repository.
Above is an illustration of the structure and components of an expression, including the focus concept, attributes and attribute value.
Expressions, Post-coordination tools and resources
The expressions have been authored using the following resources and validated against the April 2024 Release of SNOMED International;
- Machine Readable Concept Model-https://browser.ihtsdotools.org/mrcm/?branch=MAIN%2F2020-07-31
- Postco-ordination demonstrator - expression validation (classification) -Postcoordination Implementation Demo (ihtsdo.github.io)
- Practical Guide to Post-coordination -https://snomed.org/postcoordination
- SNOMED International browser
HPO to SNOMED Cross Mapping - the results
Based on the HPO release of August 2024, and the SNOMED International release of April 2024, the mapping results are given below.
Note that 86% of the HPO terms are mappable either directly or involving an expression, and the missing 13% could potentially be reduced with new SNOMED content.
The expressions have been validated using the Post-coordination Demonstrator resource. (Postcoordination Implementation Demo (ihtsdo.github.io))
| Group | Number (%) |
|---|---|
| One to one map | 7239 (41%) |
| One to many | 81 (0.5%) |
| Map with expression | 7952 (45%) |
| Map to parent | 2380 (13.5%) |
| Clarification | 22 (0.1%) |
| Out of scope | 696 (3.9) |
| Total | 18,370 |