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Negative predictive value
Introduction
Assistant Editor(s)-In-Chief: Kristin Feeney, B.S.
Overview
Overview
The negative predictive value is the proportion of individuals without preclinical disease who test negative using the specified testing modality.
Definition
Definition
The Negative Predictive Value can be defined as:[1]
<math> NPV = \frac{\rm number\ of\ True\ Negatives}{{\rm number\ of\ True\ Negatives}+{\rm number\ of\ False\ Negatives}}</math>
or, alternatively,
<math> NPV = \frac{({\rm specficity}) ({\rm 1 – prevalence})}{({\rm specificity}) ({\rm 1 – prevalence}) + (1 – {\rm sensitivity}) ({\rm prevalence})} </math>
References
References
- ↑ Altman DG, Bland JM (1994). “Diagnostic Tests 2 – Predictive Values”. British Medical Journal. 309 (6947): 102. Unknown parameter
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