Medical subject headings (MeSH) terms

We publish 3-10 keywords like most of the journals, at the end of abstract of manuscripts. Those reflect the contents of the manuscript and facilitate the search of relevant literature. Well chosen keywords enable manuscript to be easily identified and cited. The representative keywords should be such that, if we feed these words, the article or the book contents can be retrieved. The problem with keywords is that they are not uniformed. Key words are generated by authors, which cannot be exact words as in contents; can vary from author to author. Thus may not retrieve similar articles by the authors who are searching the relevant literature. Therefore, if keywords are used, the citation of your article may miss, affecting citation index. We felt the need to have uniformed subject headings (keywords) to increase the citation and help authors to retrieve wholesome literature on a particular subject. Medical subject headings (MeSH) terms were introduced by National Library of Medicine (NLM), United States in 1963.¹

Medical subject headings terms are controlled specialized vocabulary (Thesaurus#), created and regularly updated by NLM, United States.²,³ These terms are used for the purpose of indexing journal, cataloging and searching for biomedical articles and books.²,⁴

This yearly printed version of MeSH was discontinued in 2007 and MeSH is now available online only.² The files are uploaded on every Sunday. The 2014 version of MeSH contains a total of 27,149 subject headings called descriptors.³ It also contains 219,000 headings called supplementary concept records³ within a separate thesaurus. Hence, MeSH terms are the list of standardized subject headings (previously similar to key words). When these standardized terms are used to search a topic, all those articles indexed in MEDLINE and NLM'S PubMed, are retrieved resulting in increase of citations of the article. Originally MeSH terms were in English, and now they have been translated in other languages as well.

Whenever the MeSH terms are used to search a topic, the database explores accordingly and in case the terms entered is not a standard MeSH, then the database will not find matches and search results would be a poor yield.⁵ We have decided to use MeSH terms to increase citation of our journal's articles. Initially, we will be using both keywords and MeSH terms. Once authors and our editorial staff become familiar in the use of MeSH terms, we shall regularly be using MeSH terms only.

Medical subject headings data can be obtained from the MeSH website http://www.nlm.nih.gov/mesh. Table 1 describes useful information about MeSH.²

Table 1.

Medical subject headings

MEDICAL SUBJECT HEADINGS TREE STRUCTURE

The MeSH tree structures are hierarchical display so that broader and narrower “descriptors” are displayed. The highest level of the MeSH tree structure consists of 16 broad categories. These terms are not put for MeSH data as maintained and distributed. However, they can be used to search PubMed by use of the search word “category.” For example search anatomy category, will retrieve all citations indexed to any MeSH descriptor in any of “A” category (anatomy).

When using a MeSH descriptor to search, PubMed automatically searches narrower Descriptors intended under it in the MeSH tree structures. Thus, for example, searching musculoskeletal neoplasm Ewings sarcoma, you will find following two trees displayed with catalogue number called tree numbers.

TREE NUMBER (S)

C04.557.450.565.575.650.800

C04.557.450.795.620.800

A user might begin the search with Ewings sarcoma but realizes after viewing hierarchy that they really wanted sarcoma. He can get a complete search on sarcoma. Thus with single MeSH word anything in the tree can be traced out.

MEDICAL SUBJECT HEADINGS TREE OF EWINGS SARCOMA

• Neuroectodermal Tumors, Primitive, Peripheral

  • All MeSH Categories
  • Diseases Category
  • Neoplasms (C04)
  • Neoplasms by Histologic Type (C04.557)
  • Neoplasms, Connective and Soft Tissue (C04.557.450)
  • Neoplasms, Connective Tissue (C04.557.450.565)
  • Neoplasms, Bone Tissue (C04.557.450.565.575)
  • Osteosarcoma (C04.557.450.565.575.650)

• Sarcoma, Ewing (C04.557.450.565.575.650.800)

  • All MeSH Categories
  • Diseases Category
  • Neoplasms (C04)
  • Neoplasms by Histologic Type (C04.557)
  • Neoplasms, Connective and Soft Tissue (C04.557.450)
  • Sarcoma (C04.557.450.795)
  • Osteosarcoma (C04.557.450.795.620)

• Sarcoma, Ewing (C04.557.450.795.620.800)

^#A book of selected words or concepts, such as specialized vocabulary for music, medicine etc.