Free statistical calculators
Diagnostic test evaluation calculator
Instructions: enter the number of cases in the diseased group that test positive (a) and negative (b); and the number of cases in the non-diseased group that test positive (c) and negative (d).
Disease prevalence
If the sample sizes in the positive (Disease present) and the negative (Disease absent) groups do not reflect the real prevalence of the disease, you can enter the disease prevalence (expressed as a percentage) in the corresponding input box.
Next click the Test button.
Results
Statistic | Value | 95% CI |
---|---|---|
Sensitivity | ||
Specificity | ||
Positive Likelihood Ratio | ||
Negative Likelihood Ratio | ||
Disease prevalence (*) | ||
Positive Predictive Value (*) | ||
Negative Predictive Value (*) | ||
Accuracy (*) |
(*) These values are dependent on disease prevalence.
For details, see the MedCalc manual: Diagnostic test 2x2 table.
How to cite this page
- MedCalc Software Ltd. Diagnostic test evaluation calculator. https://www.medcalc.org/calc/diagnostic_test.php (Version 23.1.7; accessed February 12, 2025)