Medical ontologies are different because there are two enormous economic incentives for their adoption: billing, in the US or any private healthcare - and medic

Medical ontologies are different because there are two enormous economic incentives for their adoption: billing, in the US or any private healthcare - and medical research much of which is highly incentivized by the pharma, device, and diagnostic industries. Improving healthcare interop is not something that happens unless it is subsidized or penalized. 50 years of healthcare IT with systems that are basically the same with some new window dressing have proven that.