What is the definition of positive predictive value (PPV)?

Positive predictive value (PPV) is defined as the likelihood that a positive test result actually reflects the presence of the condition being tested for—essentially, it assesses the accuracy of a positive result. It is calculated as the number of true positive results divided by the total number of positive results (both true positives and false positives). This measure is particularly important in clinical settings because it helps clinicians understand how reliable a positive test result is when evaluating a patient for a specific disorder or disease.

By confirming that a positive test indicates the presence of a disease with high confidence, practitioners can make informed decisions regarding diagnosis and treatment. This concept is crucial in understanding the efficacy of diagnostic tests and their impact on patient care. The other choices relate to different aspects of test performance, such as specificity and sensitivity, but they do not accurately define positive predictive value.