A medical error is a preventable adverse effect of care, whether or not it is evident or harmful to the patient. This might include an inaccurate or incomplete diagnosis or treatment of a disease, injury, syndrome, behavior, infection, or other ailment. Globally, it is estimated that 142,000 people died in 2013 from adverse effects of medical treatment; this is an increase from 94,000 in 1990. However, a 2016 study of the number of deaths that were a result of medical error in the U.S. placed the yearly death rate in the U.S. alone at 251,454 deaths, which suggests that the 2013 global estimation may not be accurate.
The word error in medicine is used as a label for nearly all of the problems harming patients. Medical errors are often described as human errors in healthcare. Whether the label is medical error or human error, one definition used for it in medicine says that it occurs when a healthcare provider chooses an inappropriate method of care or improperly executes an appropriate method of care. It has been said that the definition should be the subject of more debate. For instance, studies of hand hygiene compliance of physicians in an ICU show that compliance varied from 19% to 85%. The deaths that result from infections caught as a result of treatment providers improperly executing an appropriate method of care by not complying with known safety standards for hand hygiene are difficult to regard as innocent accidents or mistakes. At the least, they are negligence, if not dereliction, but in medicine they are lumped together under the word error with innocent accidents and treated as such.
There are many types of medical error, from minor to major, and causality is often poorly determined.
There are many taxonomies for classifying medical errors.
Globally, it is estimated that 142,000 people died in 2013 from adverse effects of medical treatment; in 1990, the number was 94,000.
A 2000 Institute of Medicine report estimated that medical errors result in between 44,000 and 98,000 preventable deaths and 1,000,000 excess injuries each year in U.S. hospitals. In the UK, a 2000 study found that an estimated 850,000 medical errors occur each year, costing over £2 billion.