Hospital visitors as controls in case-control studies
نویسندگان
چکیده
منابع مشابه
Hospital visitors as controls in case-control studies.
OBJECTIVE Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted...
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ژورنال
عنوان ژورنال: Revista de Saúde Pública
سال: 2001
ISSN: 0034-8910
DOI: 10.1590/s0034-89102001000500005