A compound attribute that is the ratio of amount of proheparin-binding EGF-like growth factor (human) in blood to amount of platelet-derived growth factor subunit B (human) in blood. The trait is Ontology of Biological Attributes id OBA_2053003 (HBEGF/PDGFB protein level ratio in blood). Also known as: the ratio of amount of proheparin-binding EGF-like growth factor (human) in blood to amount of platelet-derived growth factor subunit B (human) in blood.