A new metadata element set based on Dublin Core Metadata Element Set (DC) and Admin-Core: Administrative Container Core (A-Core) was proposed for Evidence Based Medicine (EBM) sources after reviewing metadata elements and contents of current EBM sources and medical metadata for Internet resources. The metadata schema was designed to provide a common format for existing primary and secondary studies; further for Internet resources as prospective sources. An enhanced DC.Description element can store structured abstracts of primary studies in primary and secondary studies of clinical research; A-Core elements are used for indexers or creators of metadata for primary studies. Two encoding schemes were suggested as EBM qualifiers for the DC.Subject element to distinguish important factors of EBM practices: the degree of evidence and focuses of clinical perspectives such as therapy, diagnosis, prognosis, and etiology. An additional feature of this metadata schema is in distinction of a variety of "types" (e.g., study type, resource type, format, genre)