ABSTRACT
Introduction: Cumulative Sum (CUSUM) technique is an objective statistical method used in assessing and monitoring doctor’s performance. It has been incorporated into quality improvement strategies in clinical services by the Ministry of Health, Malaysia. A pilot study was aimed at evaluating its usefulness in monitoring the performance of specialists in conducting skin biopsy. Methods: All skin biopsies performed by specialists in the Department of Dermatology, Kuala Lumpur Hospital from September 2009 to April 2011 were included in the prospective observational study. Outcomes monitored were wound complications within 14 days post-biopsy, and tissue sample being adequate and representative for histopathological interpretation. CUSUM scores of each consecutive biopsy performed by individual specialist were calculated and charted with the eCUSUM web application (https://app.acrm.org.my/eCUSUM). Results: A total of 870 skin biopsies were performed by 15 clinical specialists and three consultant dermatologists during the study period. Wound infection or dehiscence were reported in 13 (4.1%) of the 318 biopsy wounds evaluated. Tissue samples were inadequate in 10 (1.2%) and non-representative in 11 (1.3%) of the 817 histopathological reports evaluated. No learning curve was observed in all CUSUM charts indicating that all specialists had been adequately trained for the procedure. However, out-of-control signals indicating unacceptable wound complication rates and either inadequate or non-representative tissue samples were detected in three clinical specialists. Feedback and counseling were given while monitoring was continued. Conclusions: The CUSUM method is a useful performance monitoring tool which is able to promptly detect unacceptable outcomes in skin biopsy. It is invaluable in the supervision of junior doctors and trainees as well as self-monitoring for the trained specialists.