Patient misidentification in laboratory medicine: a qualitative analysis of 227 root cause analysis reports in the...

Mislabeled laboratory specimens are a common source of harm to patients, such as repeat phlebotomy; repeat diagnostic procedure, including tissue biopsy; delay in a necessary surgical procedure; and the execution of an unnecessary surgical procedure. Mislabeling has been estimated to occur at a rate of 0.1% of all laboratory and anatomic pathology specimens submitted.

To identify system vulnerabilities in specimen collection, processing, analysis, and reporting associated with patient misidentification involving the clinical laboratory, anatomic pathology, and blood transfusion services.

A qualitative analysis was performed on 227 root cause analysis reports from the Veterans Health Administration. Content analysis of case reports from March 9, 2000, to March 1, 2008, was facilitated by a Natural Language Processing program. Data were categorized by the 3 stages of the laboratory test cycle.

Patient misidentification accounted for 182 of 253 adverse events, which occurred in all 3 stages of the test cycle. Of 132 misidentification events occurring in the preanalytic phase, events included wrist bands labeled for the wrong patient were applied on admission (n = 8), and laboratory tests were ordered for the wrong patient by selecting the wrong electronic medical record from a menu of similar names and Social Security numbers (n = 31). Specimen mislabeling during collection was associated with "batching" of specimens and printed labels (n = 35), misinformation from manual entry on laboratory forms (n = 14), failure of 2-source patient identification for clinical laboratory specimens (n = 24), and failure of 2-person verification of patient identity for blood bank specimens (n = 20). Of 37 events in the analytic phase, relabeling all specimens with accession numbers was associated with mislabeled specimen containers, tissue cassettes, and microscopic slides (n = 27). Misidentified microscopic slides were associated with a failure of 2-pathologist verification for cancer diagnosis (n = 4), and wrong patient transfusions were associated with mislabeled blood products (n = 3) and a failure of 2-person verification for blood products before release by the blood bank (n = 3). There were 13 events in the postanalytic phase in which results were reported into the wrong patient medical record (n = 8), and incompatible blood transfusions were associated with failed 2-person verification of blood products (n = 5).

Patient misidentification in the clinical laboratory, anatomic pathology, and blood transfusion processes were due to a limited set of causal factors in all 3 phases of the test cycle. A focus on these factors will inform systemic mitigation and prevention strategies.