Aims: To apply cumulative sum (CUSUM) in monitoring performance of surgeons in cataract surgery and to evaluate the response of performance to intervention.
Method: CUSUM analysis was applied to 80 phacoemulsification performed by three ophthalmic trainees and one consultant, in the occurrence of posterior capsular rupture and post-operative refracted vision of worse than 6/12 among patients without pre-existing ocular co-morbidity. CUSUM score of each consecutive procedure performed by an individual surgeon was calculated and charted on CUSUM chart. When trainees’ CUSUM charts showed an unacceptable level of performance, their supervisors would give feedback and impose closer monitoring of subsequent surgeries.
Results: CUSUM charts of the trainees demonstrated an initial upward followed by flattening trend reflecting learning curves in their process of acquiring competency in phacoemulsification. In contrast, the consultant showed a flat curve indicating an ongoing maintenance of competence.
Conclusion: CUSUM analysis is able to monitor and promptly detects adverse event and trend of unacceptable outcome of cataract surgery. This objective and dynamic monitoring makes CUSUM a useful audit tool, not only for individual surgeons but more so for busy consultants who need to supervise trainees.