This element intends to represent the evidence for an assertion such as an observation of a PhenotypicFeature. We recommend the use of terms from the Evidence & Conclusion Ontology (ECO)

Data model

Definition the Evidence element
Field Type Status Description
evidence_code OntologyClass representing ECO:0006017 required An ontology class that represents the evidence type
reference ExternalReference optional Representation of the source of the evidence


  "evidenceCode": {
    "id": "ECO:0006017",
    "label": "author statement from published clinical study used in manual assertion"
  "reference": {
    "id": "PMID:30962759",
    "description": "Recurrent Erythema Nodosum in a Child with a SHOC2 Gene Mutation"


For example, in order to describe the evidence for a phenotypic observation that is derived from a publication, one might use the ECO term author statement from published clinical study used in manual assertion (ECO:0006017) and record a PubMed id in the reference field (See ExternalReference).


An ExternalReference is used to store a reference to the publication or other source that supports the evidence. Not all types of evidence will have an external reference, and therefore this field is optional.