Selection of MEDLINE contents, the development of its thesaurus, and the indexing process.

The operation of MEDLINE requires three ongoing activities by persons having subject matter knowledge. These are literature selection, thesaurus maintenance and indexing. MEDLINE is intended to give access to the most generally useful biomedical literature rather than to provide indiscriminate comprehensive coverage. Literature is selected with the guidance of a group of health-science educators, editors and librarians who review periodicals under consideration for inclusion and re-evaluate those that are already regularly indexed. The MeSH thesaurus provides the descriptors that are used for subject indexing. Its hierarchical structure facilitates both general and specific searching. The appearance of new concepts and terminology in the literature requires a dynamic MeSH, but MeSH changes may complicate the process of searching backward in time. Maintaining MeSH requires finding a balance between the need for adaptability and the need for stability. Quality indexing requires accuracy and consistency in the assignment of subject headings. To this end, indexers receive didactic training plus practice under supervision. Precedents for indexers are detailed in an extensive Indexer's Manual and in MeSH annotations. Work of all indexers is reviewed on at least a sampling basis, and special sessions are held each year to familiarize indexers with MeSH changes.

Gynecology: an etymological note.

"Gynecology" is derived ultimately from the Indo-European root GEN-. Though this gives directly words like progeny and generate, by a less open path come the Latin cognates like nature and native and the English queen and king. "Woman" is explained, and English names like Brewster are explained with reference to the suffix -ster. Latin derivatives of the female/feminine class are traced to an old root DHE, cognate with the Greek derivatives involving thel-. Short stories are told for virago, amazon, mamma, barbarian, abecedarian, elementary, and for many Latin-derived words in mol- and English words in mil-, tying them to the Latin mollis (soft) as related to mulier (woman). These are tied, in turn, to an older root MAR-yielding marasmus, mors, murder, milk, etc. Derivatives from the Latin domina and finally the English lady are discussed.

MEDLARS abbreviations for medical journal titles.

The National Library of Medicine announces its adoption of the Anglo-American standard for the formulation of journal title abbreviations according to the American National Standard for the Abbreviation of Titles of Periodicals (1969), with individual words abbreviated, in turn, according to the International List of Periodical Title Word Abbreviations (1970). The history of the activity of the specific Z39 Committee of USASI (now ANSI) concerned with journal title abbreviations is reviewed, covering the period from 1962 to the present. A history of the National Clearinghouse for Periodical Title Word Abbreviations and of the International List is also given. Former NLM usage is compared with the forms of the present International List and examples show the major changes in NLM abbreviations. The NLM Rules for Abbreviation of Periodical Titles as derived from the new standard are appended.