Which way for a classification scheme for computers and medicine

The National Library of Medicine supports an extensive collection of online indexed document citations for the biomedical field, The indexing scheme, although one of the first of its kind, remains one of the most sophisticated in everyday usage. The 14,000 terms of the Medical Subject Headings (MESH) are organized in a hierarchy of "is-a" relations that constitute a very simplified knowledge-base of the biomedical literature.