Patient misidentification in Papanicolaou tests: a systems-based approach to reducing errors.

CONTEXT: Patient safety is of prime concern in every laboratory. Double labeling of glass slides is performed in many cytology laboratories where handwritten patient information on the frosted portion of the glass is overlaid with paper labels (sometimes containing bar codes). The cytotechnologists match this information by turning slides over. We use SurePath liquid-based cytology for Papanicolaou tests in our laboratory and noticed patient misidentification because of slide labeling errors, a problem that has not been addressed in the literature.

OBJECTIVE: To reduce slide labeling errors without increasing costs, using a systems-based approach.

DESIGN: All errors from mislabeled slides during November 2006 were documented, and an informal root-cause analysis was performed. Slides were labeled on opposite ends and monitored for errors.

RESULTS: Labeling on different ends of the glass slide reduced our error rate from 0.59% to 0%, made visual matching easy, and did not alter costs.

CONCLUSIONS: The practice of overlaying handwritten information with printed labels for liquid-based Papanicolaou tests should be strongly discouraged and replaced with placing patient information in separate portions of the glass slide so that crucial patient identification is not hidden and visual matching is easy.