Table of Contents: 2015 NOVEMBER–DECEMBER No. 407
Schulman J. What's New for 2016 MeSH. NLM Tech Bull. 2015 Nov-Dec;(407):e9.
MeSH is the National Library of Medicine controlled vocabulary thesaurus which is updated annually. NLM uses the MeSH thesaurus to index articles from thousands of biomedical journals for the MEDLINE/PubMed database and for the cataloging of books, documents, and audiovisuals acquired by the Library.
Please consult the 2016 online Introduction to MeSH for more details. Lists of new and changed vocabulary are available at these links:
In addition to responding to requests we have been working on projects that are designed to improve the MeSH vocabulary. Several of these projects were directed towards to revamping our MeSH tree structure to make it easier to understand.
In order to improve indexing consistency and efficiency and to make MEDLINE searching easier and more straightforward, the subheading diagnostic use was deleted from MeSH. See the MeSH Qualifier (Subheading) Deletion section of the MEDLINE Data Changes — 2016 article for additional information.
Three Publication Types were added for catalogers:
One Publication Type was added mainly for use by indexers:
See the MeSH Publication Types section of the MEDLINE Data Changes — 2016 article for additional information.
In the past, MeSH headings were loosely organized in trees and could appear in multiple locations depending upon the importance and specificity. In some cases the heading would appear two or more times in the same tree at higher and lower levels. This arrangement led to some headings appearing as a sibling (uncle) next to the heading under which they were treed as a nephew. In other cases a heading was included at a top level so it could be seen more readily in printed material. We reviewed these headings in MeSH and removed either the Uncle or Nephew depending upon the judgement of our Internal and External reviewers. There were over 1,000 tree changes resulting from this work, many of which will affect search retrieval in MEDLINE/PubMed and the NLM Catalog.
The M01 tree in MeSH is devoted to persons as individuals or members of a group, while the H tree contains the Disciplines and Occupations (professions). Although this premise held true for most cases we had a large number of exceptions where people were listed as an entry term under their profession. In addition the subheading manpower was used with a profession to indicate the person when a heading for them was not available. We felt this inconsistency required too much effort on the part of searchers to determine where to look and what to do. We simplified the trees by moving all people from the Professions tree and created new headings for them in the Persons tree.
The J02 tree in MeSH includes food items, while the B tree contains plants and animals. For many years the fact that some plants and animals are also treed under food has been source of confusion for searchers. We received many requests to add and subtract specific plants from food that were based upon conflicting sources of information. In addition the range of exotic plants being eaten has expanded over the years. To respond to these problems we made major changes to the organization of nutritional phenomena for the 2016 Medical Subject Headings.
Nutritionally-related descriptors were brought together for the MeSH descriptor "Diet, Food, and Nutrition" that was created in the G07 tree. The descriptors "Diet" and "Nutritional Physiological Phenomena" along with their child descriptors were moved there. In addition a second tree location for "Food and Beverages" and its child descriptors were added there. Specific plant and chemical headings were removed from underneath "Food and Beverages" because many of the citations indexed with them were not about food or nutritional topics. As a result, searching "Food and Beverages" or "Diet, Food, and Nutrition" now gives a more focused retrieval of citations that are nutritionally related. Articles that discuss a specific plant or chemical in the context of food can still be found through use of coordination of topics rather than using tree inheritance. For example, a search in the 2016 PubMed system to find specific citations about the nutritional value of spinach can now be done as:
MeSH had a policy that each descriptor should have a scope note regardless of how obvious its meaning. There were many legacy headings that were created without scope notes before this rule came into effect. This year we initiated a project to write scope notes for all existing headings. Thus far 481 scope notes to MeSH were added and the project continues for 2017 MeSH.
The MeSH Section received requests that high profile pharmaceutical drugs be made as descriptor records, rather than keeping them as Supplementary Concept Records (SCRs). We prepared a list of 150 top prescribed drugs and compared them to MeSH. All drugs on this list that were represented by SCRs were promoted to descriptor headings.