This article looks at the operationalization of race and ethnicity concepts in
medical classification systems, notably the main bibliographical databases of
MEDLINE and EMBASE. In particular, an attempt is made to assess recent changes,
including the impact of the 2004 major changes to the MeSH headings for race and
ethnic groups, and the introduction of 'Continental Population
Groups'. The underlying conceptual basis of the typologies, their relevance for
capturing specific population groups, and their overall usefulness in appraising
the literature on ethnic/racial disparities in health are examined. The
bibliographical database thesauri reveal the pervasiveness of the notion of the
biological basis of health differences by race/ethnicity as well as continuing
use of antiquated racial terminology. Their system-oriented terminology is
likely to limit the effectiveness of retrieval by users who may lack knowledge
of their hierarchical structures.