Skip to content


It is very common that there are multiple datasets for similar data domains. For example, the Human Disease Ontology (DOID) as well as the National Cancer Institute Thesaurus (NCIT) both cover the domain of diseases. Both contain a Reference Entity for the disease 'melanoma' with identifiers obo:DOID_1909 and ncit:C3224 respectively.

A mapping is a statement about the similarity of two different Reference Entities. For example, DOID contains the Mapping Statement obo:DOID_1909 oboinowl:hasDbXref ncit:C3224 where oboinowl:hasDbXref is used as the Mapping Property.

Mapping Triple

In this example, the mapping is an Outgoing Reference for obo:DOID_1909 and an Incoming Reference for ncit:C3224. In general, outgoing mappings go from the currently selected entity to others, while incoming mappings are references from other entities. All mappings related to a given entity can be viewed as part of the Mappings View.

Mapping Properties

Accurids detects the configured mapping properties and displays corresponding statements in the Entity Details view as Outgoing or Incoming Mappings. Detailed information on how to manage mapping properties can be found here (../admin-guide/

Strong and Weak Mappings

  • Strong mappings are mapping statements where the target entity is expressed through an Internationalized Resource Identifier (IRI); e.g., obo:DOID_1909 oboinowl:hasDbXref ncit:C3224.
  • Weak mappings are mapping statements where the target entity is represented through a string instead of an IRI; e.g., obo:DOID_1909 oboinowl:hasDbXref "NCI:C3224"^^xsd:String.