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MEDLINE Indexing Online Training Course

Category E - Techniques and Equipment

Indexing Principles

A technique will be indexed under the following circumstances:

  1. The technique appears in the title or statement of purpose for the article.
  2. The technique is discussed in the text of the article and not merely mentioned in the materials and methods
  3. The technique described is novel, or the application of the technique is new.
  4. The technique is described in a journal devoted to techniques (such as Electrophoresis, Chromatography, Journal of Electron Microscopy, etc)

Category E terms are usually NIM concepts; however there are some circumstances where the technique term should be IM:

  1. If the technique is the main point of the article, it will be indexed IM.
  2. Diagnostic and therapeutic techniques in clinical articles will likely be IM concepts.
  3. A new technique or a new application of an existing technique will probably be IM.
  4. In journals devoted to techniques, the technique will likely be IM.


Magnetic resonance imaging for the diagnosis of multiple sclerosis.
(The point of the article is the use of MRI in the diagnosis of multiple sclerosis.)
Antibodies to Escherichia coli in the serum of patients with E. coli infections.
(The materials and methods states that the antibodies were measured by immunoblotting and the immunoblots are shown in figures in the results. Immunoblotting is indexed NIM.)
E COLI / * immunol
HUMAN (check tag)

Last Reviewed: January 23, 2017