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## Negative Predictive Value

Aka: Negative Predictive Value
2. Definition
1. Patients with negative test that do not have disease
2. Assesses reliability of negative test
3. Indications
1. Puts Test Sensitivity in context of disease Prevalence
2. Lower disease Prevalence results in higher NPV
1. Test Sensitivity effect minimized at low Prevalence
2. False negatives decrease substantially
3. Results in more reliable negative test
4. Calculation
1. NPV = (True negative) / (true and false negatives)

### Negative Predictive Value of Diagnostic Test (C1513918)

Definition (NCI) The probability that an individual is not affected with the condition when a negative test result is observed. This measure of accuracy should only be used if the data on the prevalence of condition of interest in given population is available. NPVDT can be determined by calculating: number of true negative results divided by the sum of true negative results plus number of false negative results.
Definition (NCI) The likelihood that an individual with a negative test result is truly unaffected and/or does not have the particular gene mutation in question.
Concepts Quantitative Concept (T081)
English NPV, negative predictive value, Negative Predictive Value of Diagnostic Test
Sources
Derived from the NIH UMLS (Unified Medical Language System)