Preliminary Requirements

• Snorocket is a reasoner/incremental classifier for SNOMED CT that will be used in the prototype
• The input of Snorocket will be a post-coordinated expression (PCE) and the output will be a single code
• A post-coordinated expression can sit in the name or value field in a FHIR resource (or any field that can
• hold a codeable concept)
• In the FHIR object, the Name field is “what is being observed" and the value field is the answer or amount
• Single identifier will correspond to a single concept within the classification taxonomy
• There is a many-to-one relationship between a PCE and a concept in the classifier
• There is only one PCE in an observation
• The Name field in a FHIR object will be a codeable concept; the Value field can be either a codeable
• concept or a string value
• Snorocket is a Java library
• FHIR and LEGOs are similar in that they are both XMLs, but FHIR can be used for more than just clinical
• observations (but our focus is just on the FHIR observables)
• A post-coordinated expression is made up of a combination of multiple SNOMED CT codes that build
• a clinical idea