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MEDLINE Indexing Online Training Course

Category Z - Geographic Locations

Subheadings

Only two subheadings are permitted with Category Z terms: /epidemiology and /ethnology.

/epidemiology is used with Category Z headings to indicate geographic location when the epidemiological aspects of a disease are discussed.

Prevalence of dengue fever in India
DENGUE FEVER /*epidemiol
INDIA /epidemiol
PREVALENCE
HUMAN (check tag)

/ethnology is used with Category Z headings to indicate the place of origin of a group of people living elsewhere.

Incidence of depressive disorders among Vietnamese immigrants in the United States
DEPRESSIVE DISORDERS /*ethnol
VIETNAM /ethnol
UNITED STATES /epidemiol
*IMMIGRANTS
INCIDENCE
HUMAN (check tag)

In the above example, Vietnamese patients were living NOT in their country of origin, but elsewhere. An article on the incidence of depressive disorders in Vietnam would be indexed as:

DEPRESSIVE DISORDERS /*epidemiol
VIETNAM /epidemiol
INCIDENCE
HUMAN (check tag)
(NOT VIETNAM /ethnol)

Last Reviewed: March 10, 2015