ERBB2/PTPRF protein level ratio in blood (OBA_2054732, an Ontology of Biological Attributes entry) can be described as follows. A compound attribute that is the ratio of amount of receptor tyrosine-protein kinase erbB-2 (human) in blood to amount of receptor-type tyrosine-protein phosphatase F (human) in blood. Also known as: the ratio of amount of receptor tyrosine-protein kinase erbB-2 (human) in blood to amount of receptor-type tyrosine-protein phosphatase F (human) in blood.