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Predictive Value Calculator

Instructions:  1. Enter data for True Positives (TP), False Positives (FP),
True Negatives (TN), and False Negatives (FN).
2. Click the 'Calculate' button.
3. Results will appear in the lower half of this page.

 

Number of True Positives (TP)
Number of False Positives (FP) 
Number of True Negatives (TN) 
Number of False Negatives (FN) 

Total  (n)
 
Sensitivity (%)  TP / (TP + FN)
Specificity (%)  TN / (TN + FP)
Positive Predictive Value (%)  TP / (TP + FP)
Negative Predictive Value (%)  TN / (TN + FN)
Prevalence  TP / n
 
Bayesian PPV (%)  (Sensitivity * Prevalence) / 
((Sensitivity * Prevalence) + ((1 - Specificity) * (1 - Prevalence)))
Bayesian NPV (%)  ((Specificity * (1 - Prevalence)) / 
((1 - Sensitivity) * Prevalence) + (Specificity * (1 - Prevalence)))