Errors encountered in the diagnostic pathway: A prospective single-institution study.

The most common error involved an incorrect biopsy site at the clinical stage. Over two-thirds of errors occurred before the slide reached the dermatopathologist. Diagnostic errors (analytical phase) rarely occurred, and when they did occur, the clinician was most likely to discover the error. Examining and addressing common laboratory errors help to reduce their incidence and lead to quality improvement in dermatopathology.