[Correlation between adenoma detection rate and advanced adenoma detection rate]

Adenoma detection rate (ADR) is widely used as an index of colonoscopy quality management. Although advanced adenomas can be found less frequently than non-advanced adenomas, advanced adenomas have a higher clinical significance during screening for colorectal cancer. The aim of this study was to investigate the correlation between advanced and non-advanced ADR among colonoscopists.

This study is an observational study of a cohort of patients undergoing screening colonoscopy between 2009 and 2010. We collected the data on patients' characteristics and colonoscopic findings. The detection rates of adenoma and advanced adenoma were calculated. Logistic regression was used to determine the effects of variables on advanced adenoma detection, and spearman's rank-order correlation was used to evaluate the relationship between advanced ADR and ADR.

A total of 561 patients underwent screening colonoscopy by 18 experienced colonoscopists. Most colonoscopists had adequate (>20%) ADRs. Logistic regression showed that increased patient age (OR 1.07 per 1 year increase, 95% CI 1.009-1.133, p=0.023) and male gender (OR 1.860, 95% CI 0.764-4.529, p=0.171) were associated with advanced ADR. When colonoscopists were divided into two groups on the basis of advanced ADR of 5%, ADR was also significantly higher in the group having higher level of advanced ADR. However, there was no correlation between advanced ADR and ADR among colonoscopists as an individual.

Colonoscopists' advanced ADRs were independent of their ADRs, indicating that advanced ADR could be quite low even among colonoscopists with acceptable ADRs. Thus, there seems to be a limitation in using ADR as an adequate index of colonoscopy quality management.