Adverse Events

Adverse events are injuries to patients caused by medical treatment. Medical errors are mistakes in medical care that may or may not harm a patient. Identifying adverse events and evaluating their causes are important parts to any strategy to reduce harm to patients. Several recent GAO reports have considered surveillance systems for medical products, particularly drugs and medical devices. (See GAO/HEHS-00-21, Jan. 2000, and GAO/HEHS-97-21, Jan. 1997.) GAO testified that although adverse events are recognized as a serious problem, the full magnitude of their threat to the American public is unknown. At the same time, gathering valid and useful information on adverse events is extremely difficult. For example, systems that rely on health care providers to take the initiative to make a report suffer from serious limitations. Moreover, many of the injuries that patients suffer as a result of medical treatment do not stem from errors but reflect the inherent risks of treatments that are administered correctly. It can be difficult to identify these adverse reactions and distinguish them from medical errors or from the course of a patient's underlying illness.

GAO noted that: (1) the results of GAO's work have important implications for addressing adverse medical events including the design of surveillance systems to detect adverse events and medical errors; (2) while adverse events have been recognized as a serious problem, the full magnitude of their threat to the health of the American public is unknown; (3) gathering valid and useful information about adverse events is extremely difficult; (4) all systems that rely on health care providers to take the initiative to make a report--known as passive or spontaneous reporting systems--have serious limitations; (5) this is true whether or not providers are legally required to report adverse events; (6) both mandatory and voluntary spontaneous reporting systems share this limitation; (7) many of the injuries patients suffer as a result of medical treatment do not stem from errors but reflect the inherent risks of treatments that are administered correctly; and (8) it can be difficult both to identify these adverse reactions and distinguish them from medical errors or from the course of a patient's underlying illnesses.