OLDMEDLINE Citations

• These citations are to articles from international biomedical journals covering the fields of medicine, preclinical sciences, and allied health sciences.
  
  
• The approximately 1.8 million OLDMEDLINE citations, most without abstracts, were originally printed in hardcopy indexes published from 1949 through 1965.
  
  
• OLDMEDLINE citations have been created using standards that are different from the data entry standards for MEDLINE records. There are also variations among OLDMEDLINE citations in the data fields present as well as in their format, depending on the original source from which the citations were obtained.
  
  
• Beginning in 2005, the original subject terms applied to the citations in the printed indexes are being mapped to current Medical Subject Headings (MeSH®).
  
  
• OLDMEDLINE records carry the status tag [PubMed - OLDMEDLINE] until all original subject terms are mapped to current MeSH. Once all terms are mapped, the records are promoted to status [PubMed - indexed for MEDLINE].