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NLM Classification Updated, September 23, 2019

September 23, 2019

The NLM Classification, available online at https://www.nlm.nih.gov/class/, is updated two times a year.

The 2019 winter version, published January 31, 2019, encompassed changes to the NLM Classification resulting from new and changed 2019 Medical Subject Headings (MeSH) terms as well as additional minor updates to the index and schedule.

The 2019 summer version, published September 23, 2019, encompasses the systematic review of the QW (Microbiology. Immunology) and QX (Parasitology) schedules and other miscellaneous updates.

For more information about the scope of the 2019 summer edition, see https://www.nlm.nih.gov/class/Scope.html.

Contact NLM for further information, questions, or comments.

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The National Library of Medicine (NLM) is a leader in research in biomedical informatics and data science and the world’s largest biomedical library. NLM conducts and supports research in methods for recording, storing, retrieving, preserving, and communicating health information. NLM creates resources and tools that are used billions of times each year by millions of people to access and analyze molecular biology, biotechnology, toxicology, environmental health, and health services information. Additional information is available at https://www.nlm.nih.gov.

Last Reviewed: September 23, 2019