Medical Subject Headings
- Understanding MARC Authority Records: Machine-Readable Cataloging. This information is from the US Library of Congress. It gives a general overview of MARC Authority Records and how they are used.
MeSH/MARC file release dates
- The annual MeSH/MARC files are released in November prior to the calendar year of their intended use. The November change file includes all the culmulative changes for the past year.
- If MeSH data changes in the middle of the year these changes will appear in the monthly full file and a change file with these changes will be made available. Note, that these monthly change files will include only changes made during that month and are not cumulative so you most load each one in sequence to get all the changes.
MeSH/MARC File Formats
- MARC Sample file
- This is a smaller file primarly used for testing and evaluation purposes. It contains 41 descriptor records, 82 qualifier records, and 869 descriptor/qualifier combinations, for a total of 993 records. Download sample file
- MARC sample label file
- This file provides size and other statistics for the matching sample data file. Download label file
- Update-only files
- These files contain new and modified terms with descriptor records and descriptor/qualifier combinations. Please remember use all the files since your last update to get all the changes.
- Update Label Files
- Provide size and other statistics for the update files.
- Full Release Files
- Contains all terms with descriptor records, qualifier records, and descriptor/qualifier combination records.
- Full Label Files
- Provides size and other statistics for the full file.
Downloading MeSH/MARC files
The data are in extended 8-bit US MARC ASCII. The files can be directly accessed via our FTP directory: ftp://nlmpubs.nlm.nih.gov/online/mesh/MESH_FILES/meshmarc/ where you can also see additional information such as file size and upload date.
MeSH/MARC File types:
- Update File
- Contains new and modified terms
- Label File
- Provides size and other statistics
- Full File
- All terms with descriptor records, qualifier records, and descriptor/qualifier combination records
Note also that starting with 2017 MESH/MARC files are prefixed with the YearMonthDate (i.e. 20160101 = Jan 1, 2016) followed by the filename.
Have questions concerning the content of MeSH/MARC files, downloading from FTP, or just want to provide feedback?
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