Diagnostic Test Accuracy (2x2 Table) Calculator
Sensitivity, specificity, predictive values and likelihood ratios.
About Diagnostic Test Accuracy (2x2 Table) Calculator
Sensitivity, specificity, predictive values and likelihood ratios. The Diagnostic Test Accuracy (2x2 Table) Calculator on Picscaler gives you the answer instantly in your browser, with no sign-up.
Inputs: True positives, False positives, False negatives and True negatives. Results shown: Sensitivity, Specificity, PPV, NPV, Accuracy, Positive likelihood ratio and Negative likelihood ratio.
Formula: Sensitivity = TP/(TP+FN); specificity = TN/(TN+FP); PPV = TP/(TP+FP); NPV = TN/(TN+FN). Predictive values depend on prevalence in the sample you tested.
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 Diagnostic Test Accuracy (2x2 Table) Calculator
- Enter True positives, False positives, False negatives and True negatives.
- Press Calculate.
- Read Sensitivity, Specificity, PPV and NPV in the result table.
- Use the formula and notes under the result to check the working.
Frequently asked questions
Is Diagnostic Test Accuracy (2x2 Table) Calculator free?
Yes. Diagnostic Test Accuracy (2x2 Table) 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.
More medical laboratory calculators
- CFU per mL Calculator - Colony count converted to CFU per mL.
- Serial Dilution Calculator - Final concentration and volumes for a dilution series.
- McFarland Standard Adjustment Calculator - Diluent needed to bring a suspension to a target turbidity.
- Log Reduction Calculator - Log10 reduction and percent reduction in microbial count.
- Bacterial Doubling Time Calculator - Generations and generation time from two counts.
- Predictive Value (PPV and NPV) Calculator - Predictive values from sensitivity, specificity and prevalence.