Consensus Development Of A Modern Ontology Of Emergency Department Presenting Problems: The HierArchical Presenting Problem OntologY (HaPPy)

 We present the HierArchical Presenting Problem ontologY (HaPPy). This ontology was empirically derived and then iteratively validated by an expert consensus panel. HaPPy contains 692 presenting problem concepts, each concept being mapped to SNOMED CT. This freely sharable ontology can help to facilitate presenting problem-based quality metrics, research, and patient care.