Online Calculators and Worksheets
These calculators and worksheets can be used in conjunction with the diagnoses and therapy cases.
Evidence-based medicine calculators
- Precision of treatment effect calculator
- Post-test probability calculator
- Diagnostic test calculator
Diagnostic test equations
| Disease present | Disease absent | |
|---|---|---|
| Diagnostic test positive | A | B |
| Diagnostic test negative | C | D |
- Sensitivity = A / (A+C)
- Specificity = D / (B+D)
- Positive predictive value = A / (A+B)
- Negative predictive value = D / (C+D)
- LR (+) = [A / (A+C)] / [B / (B+D)] = sensitivity / (1-specificity)
- LR (-) = [C / (A+C)] / [D / (B+D)] = (1-sensitivity) / specificity