Medline is the National Library of Medicine’s (NLM) premier bibliographic database covering the fields of medicine, nursing, dentistry, veterinary medicine, the health care system, and the preclinical sciences. The Medline file contains bibliographic citations and author abstracts from approximately 3,900 current biomedical journals published in the United States and 70 foreign countries. The file contains approximately 9 million records dating back to 1966. Coverage is world wide, but most records are from English-languages sources or have English abstracts.