Evaluation of diagnostic tests in parallel and in series
Valutazione in parallelo e in serie di test diagnostici multipli
Multiple diagnostic tests are often required in clinical setting, evaluating the combination of their results to diagnose a disease or a condition. Multiple tests can be performed in parallel or in series. In parallel testing, two or more tests are applied to a patient at the same time. If any of the test results are positive, then the patient is considered to be positive. In series testing, the tests are performed sequentially, but only the individuals that are positive to the initial test are retested. A patient is only considered to be positive if all tests are positive. Using tests in parallel improves the negative predictive value, as it increases the sensitivity and reduces false negatives. Using tests in series improves the positive predictive value, as it increases specificity and reduces false positives.