index patient

plural index patients

Definition of index patient

: an individual affected with the first known case of an infectious disease or genetically transmitted condition or mutation in a population, region, or family : index case sense 2

First Known Use of index patient

1951, in the meaning defined above

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The first known use of index patient was in 1951

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Last Updated

16 Mar 2020

Cite this Entry

“Index patient.” Dictionary, Merriam-Webster, Accessed 29 Mar. 2020.

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index patient


Medical Definition of index patient

: a patient whose disease or condition provides an index case

called also index case-patient

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