When flipping a coin, getting “heads” doesn’t change the odds of getting “tails” on the second flip. These two events are independent, and the probability of both happening can be found by multiplying the independent probabilities of each together.
Now consider the relationship between a troponin test and the presence of an acute MI. These two events are dependent, we can no longer consider the probabilities of each separately. Conditional probability describes the way the probability of an event (presence of acute MI) is changed by the knowledge of previous events (troponin elevated).
In this module, you can learn about conditional probability and how it relates to troponin.