Predictive Value (PPV and NPV) Calculator
Predictive values from sensitivity, specificity and prevalence.
About Predictive Value (PPV and NPV) Calculator
Predictive values from sensitivity, specificity and prevalence. The Predictive Value (PPV and NPV) Calculator on Picscaler gives you the answer instantly in your browser, with no sign-up.
Inputs: Sensitivity (%), Specificity (%) and Prevalence (%). Results shown: PPV and NPV.
Formula: PPV = Se x P / (Se x P + (1 - Sp)(1 - P)); NPV = Sp x (1 - P) / (Sp x (1 - P) + (1 - Se) x P). Shows why a good test still gives many false positives when disease is rare.
This tool is for education and information. It does not replace clinical judgement, so confirm results against your laboratory's reference ranges and local guidelines.
How to use Predictive Value (PPV and NPV) Calculator
- Enter Sensitivity (%), Specificity (%) and Prevalence (%).
- Press Calculate.
- Read PPV and NPV in the result table.
- Use the formula and notes under the result to check the working.
Frequently asked questions
Is Predictive Value (PPV and NPV) Calculator free?
Yes. Predictive Value (PPV and NPV) Calculator is completely free to use on Picscaler.
Do I need to create an account?
No. You can use it straight away without signing up.
Is my data safe?
Your input is processed in your browser on your own device and is not uploaded to Picscaler.
Can I use it for medical decisions?
No. It is an educational aid and does not replace professional medical judgement.
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