False results

Those people who have been misclassified as false positive and false negative still have a test result. If patients have disease and the test has not identified them, then they are labeled as negative, but the test is wrong so this is a false negative. Similarly, the group with no disease that did not have a negative result, must have had a positive result, so they are false positive.

Hence the population with disease includes those who have true positive test results and false negative test results.

The population without disease includes those who have true negative test results and false positive test results.