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Last Edited: 3/18/2008

What is a case report or case series?

A case report is a descriptive study of a single individual (case report) or small group (case series) in which the possibility of an association between an observed effect and a specific environmental exposure is based on detailed clinical evaluations and histories of the individual(s). They are most likely to be useful when the disease is uncommon and when it is caused exclusively or almost exclusively by a single kind of exposure (vinyl chloride and angiosarcoma or diethylstilbestrol (DES) and clear-cell carcinoma of the vagina). Case reports (or case series) may be first to provide clues in identifying a new disease or adverse health effect from an exposure.