Document Type Definitions (DTDs) for NLM Databases

The purpose of a DTD (Document Type Definition) is to define the building blocks of an XML document. It defines the document structure with a list of allowable elements. Below are the DTDs that define NLM XML data.

MEDLINE^®/PubMed^® DTD:

• pubmed_190101.dtd (01/01/19) For use with 2019 and 2020 PubMed data.

MeSH® DTDs:

• 2020 MeSH Descriptor DTD - used for MeSH Vocabulary, companion database to MEDLINE/PubMed
• 2020 MeSH Qualifier DTD
• 2020 MeSH SCR DTD
• 2020 MeSH Pharmacological Action DTD
• Please note: The 2020 DTD files are to be used with 2020 production MeSH. No structural changes have been made from the 2019 DTD files

For more information, see the Download MeSH Data page.

NLM Catalog DTD:

• NLMCatalogRecordSet DTD (01/01/20)

List of Serials Indexed for Online Users (LSIOU)

• 2020 NLM Serials DTD

HMD DTDs:

• 2013 IndexCatalogue DTD
• 2013 eTKeVK2 DTD

HSRProj:

• HSRProj DTD

Toxicology Databases:

• NLM CCRIS DTD (02/26/04)
• NLM ChemIDplus Subset DTD (04/28/05)
• NLM GENE-TOX DTD (02/11/02)
• NLM HSDB® DTD (04/12/04)
• NLM LactMed DTD (03/27/15)