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number needed to screen

— The number of people who would need to be screened over a specific period of time before one good outcome of the screening will occur

Synonyms:

NNS, NNTS

Full explanation:

The number needed to screen is an estimate of how many people need to be screened before one person would experience a good outcome.

Example:

For example, if a study found that for every 1000 participants allocated to screening for cancer there was one less death from that cancer over a period of ten years compared to every 1000 people allocated to not receive the screening test, the number needed to screen would be 1000, for ten years.

See also:

number needed to treat  ·  screening

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