Enter the pre-test probability and the likelihood ratio into the calculator to determine the post-test probability.
- Conditional Probability Calculator
- Compound Probability Calculator
- Negative Binomial Calculator
- Empirical Probability Calculator
Post-Test Probability Formula
The following equation is used to calculate the post-test probability.
Pre Test Odds = P/(1 – P) = 0.012
Post Test Odds = Pre Test Odds * LR
Post Test Probability = Post Test Odds/(1 + Post Test Odds)
- Where P is the pre-test probability
- LR is the likelihood ratio
Post-Test Probability Definition
Post-test probability as defined as the chance of an event occurring given a pre-test probability and pre-test odds.
Post-Test Probability Example
How to calculate Post-Test Probability?
- First, determine the pre test odds.
Calculate the pretest odds.
- Next, determine the likelihood ratio.
Calculate the likelihood ratio.
- Finally, calculate.
Calculate the post-test probability using the formulas above.
A post test probability is the likelihood for an event to occur given a starting pre test probability, and pre-test odds.