When health care providers are trying to determine how well a patient can function, they often just ask the patient about whether he or she has trouble with daily activities, such as eating, dressing, bathing, or walking. These types of measures are known as patient self-report. Other ways to evaluate a patient's function involve actually observing whether the patient can complete a task. These types of measures are known as performance-based tests. It is unknown which method is better for identifying patients who are having difficulty.