Background: ERCP is increasingly performed not only in large referral
centers but also in smaller units. We sought to analyze the success ra
tes of selective cannulation and intervention using the cumulative sum
method and to document the workload in a small unit. Methods: Indicat
ions, results, and interventions performed by one endoscopist were rec
orded for ail patients undergoing ERCP at Dunedin Hospital. Selective
cannulation and successful intervention were used as outcome measures
and, using the cumulative sum method, compared to a target value of 90
%. Results: Over an 8-year period, 532 ERCPs were performed. Overall 9
1% and 81% of selective cannulation and interventions respectively, we
re successful. The cumulative sum method plot shows that satisfactory
outcomes for selective cannulation were obtained after some 100 to 120
procedures and after some 120 interventions. ERCP was normal in 171 (
32%) patients, stones were found in 169 (32%), and strictures in 81 (1
5%) patients. Conclusions: The cumulative sum method is a valuable too
l to compare individual performance with a nominated target value and
to ensure that an acceptable outcome is achieved and maintained. These
results show that small units can develop and maintain expertise in E
RCP if procedures are performed regularly.