All medical tests have the potential to produce false positive and false negative results. A false positive can result in wasteful therapy, whereas a false negative can result in a mistaken diagnostic, which is extremely dangerous since a condition has been overlooked. Medical tests should be used with caution so that they do not cause more harm than good. The likelihood of a test result being true depends on how well it predicts what will happen with patients. For example, if my patient has chest pain and an elevated cardiac enzyme level is found, this means their heart muscle is damaged. The test results are called "positive." They are accurate and reliable. It is important to remember that most test results are either positive or negative. A positive result means that something is wrong with your body. A negative result means that nothing is wrong with your body. Most tests only give one answer. When interpreting test results, it is important to understand what would happen with your patient if they had the opposite diagnosis or illness. A false negative test result may lead to a delay in appropriate treatment. However, their illness may be serious, so physicians should consider other possible diagnoses before concluding there is no problem with the patient's heart.