Locators are the citations—commonly, page numbers in print indexes—that follow the entry to indicate where the material about that entry is found. Locators may also be paragraph numbers, line numbers, section numbers, volume-page number combinations, figure identifiers in atlases,8 hyperlinks in online indexes, etc. American Society of Indexers guidelines recommend that no more than 5 to 7 locators per term be given. When more than 7 locators accumulate under one heading (ie, 7 “undifferentiated locators”), the indexer should consider breaking them down under subheadings. This will produce a more usable index.11
SARS (severe acute respiratory syndrome), 18, 20, 75–79, 93,105, 117, 145–148, 167, 187–189, 235, 280, 357, 402
SARS (severe acute respiratory syndrome), 75–79, 145–148
in China, 187–189
drug therapy for
interferon alfa, 402
etiology of, 93, 105, 117
quarantine for, 167, 235
in Toronto, 280
Typographic variations on locators include bold for main discussions, t for tables (frequently used in medical indexes), f for figures, and others.
eczema, 24, 275f, 290-295, 294t
Explanatory notes are recommended when any typographic variation is used, for example, “Locators in boldface indicate main discussions. Those followed by t or f indicate tables and figures, respectively.” Such notes are most useful for the reader when they appear as running headers or footers (L. P. Wyman, email communication, February 19, 2004).