Problems of medical subject cataloging.

The subject catalog of the University of Colorado Medical Center Library is examined in considerable detail. Annual revisions of the subject catalog required by annual revisions of the subject heading authority list used, NLM's MeSH, are analyzed in terms of man-hours required for the effort and the effect on the catalog's structure. It is contended that, in a divided catalog, changes of headings on a one-for-one equivalency basis are no more difficult than they would be in a computerized catalog, but that in many-for-one changes the manual catalog and the machine catalog face exactly the same dilemma and in the same magnitude, the only solution in either case being the reexamination of many entries. The proliferation of subheadings is shown to present particularly vexing problems in catalog revision. A plea is made to recognize the MeSH system for what it is, a legitimate compromise between the descriptor-oriented terms of a computer coordinate-indexing system, and the subject-heading-oriented terms of the conventional card catalog.