Reducing Labeling Errors in Histopathology Specimens: A Quality Improvement Initiative on Endometrial vs. Endocervical Specimens to Promote Patient Safety in KK Women's and Children's Hospital.

BACKGROUND

Mislabeling of endometrial vs. endocervical curettings was the most frequent specimen error in the Division of Obstetrics & Gynaecology at KK Women's and Children's Hospital, Singapore. These look-alike/sound-alike (LASA) errors can compromise patient safety and workflow efficiency. The authors aimed to reduce specimen labeling errors over a two-year quality improvement (QI) period.

METHODS

Following root cause analysis, a multidisciplinary QI project was initiated in a single tertiary obstetrics & gynecology center using the Plan-Do-Study-Act (PDSA) methodology. Between 2020 and 2022, interventions were (1) a pilot system-level enhancement to the electronic ordering interface; (2) clinician education, training, and monthly feedback; (3) team-based process redesign emphasizing accountability and safety culture; and (4) a subsequent system-level enhancement to the electronic ordering interface during a second PDSA cycle. The primary outcome was the rate of endometrial vs. endocervical mislabeling events per 1,000 orders. The researchers plotted time-series run charts and u-charts and calculated pre- and postintervention incidence rate ratios (IRRs).

RESULTS

Among 42,968 curettings from January 2020 to May 2025, 46 endometrial/endocervical mislabeling events occurred. Mislabeling rates were 3.79 per 1,000 orders at baseline (9/2,373; January-May 2020), 3.80 between two PDSA cycles (33/8,683; June 2020-April 2021), and 0.13 following the second PDSA cycle (4/31,912; from May 2021), corresponding to a 96.7% reduction vs. baseline (IRR 0.03, 95% confidence interval [CI] 0.01-0.11, p < 0.001). Time-series charts showed a sustained special cause shift since May 2021, with 30 consecutive zero-error months between January 2022 and June 2024.

CONCLUSION

A combination of education, feedback, process audits, and interface redesign effectively addressed mislabeling of endometrial/endocervical specimens, a high-impact patient safety concern. This approach may be transferable to other LASA error domains.