Identification errors in pathology and laboratory medicine

Identification errors in the laboratory involve misidentification of a patient or a specimen. Either error has the potential to cause patients harm. Some of the more spectacular medical misadventures reported in the press involve specimen identification errors, such as a recently publicized case of an unnecessary mastectomy that resulted from the mix-up of two biopsy specimens. Anecdotal evidence suggests that identification errors occur frequently. Managers of even the smallest clinical laboratories can typically recall several identification errors that were brought to their attention during the preceding month. Some identification errors are caught in the laboratory before a result is released beyond the laboratory's walls. Other identification errors are detected by physicians or nurses who receive laboratory test results that do not make sense for a patient, or that they know were never ordered on a patient. A small number of identification errors are not detected until a patient is inconvenienced or injured. A patient may be admitted because his physician received a laboratory result belonging to another patient, receive a medication he did not need, or fail to receive treatment he required. Rarely, a patient may be permanently harmed as a result of a laboratory identification error. Approximately 25 deaths per year occur in the United States because of hemolytic transfusion reactions caused by specimen or patient identification errors; every year several patients undergo a disfiguring resection for a tumor belonging to a different patient. This review defines identification errors and discusses error detection methods, frequency of errors, measures used to prevent identification errors, and areas for further study.