During the past five years, I've been intimately involved with Shared Health and Research Electronic library (SHARE), a set of technologies the Clinical Data Interchange Standards Consortium (CDISC) uses for developing and managing industry clinical data standards.
Part of SHARE is a metadata repository that has the standards broken down into bits of metadata. Access to the SHARE repository is limited. But, the CDISC publishes the standards freely on its download site in a number of formats, including XML and RDF.
In late November 2017, while attending the annual CDISC International Interchange in Austin, I was invited to participate in a SHARE API Design workshop.