When the adenoma detection rate (ADR) was originally proposed as a quality measure in 2002, the recommendation did not constrain its indication to screening colonoscopies only. The recommendation to limit the use of ADR measurement to screening colonoscopies was made in 2006 because the target thresholds had been derived from screening studies. However, surveillance ADRs are typically higher than screening ADRs, which are higher than diagnostic ADRs, so that all 3 combined often result in an ADR close to the screening-only ADR. This was demonstrated in a previous single-center study and could lead to simplifying the ADR measurement.
In a study conducted in Veterans Affairs hospitals involving 2628 procedures, the distribution of screening examinations was 29%, surveillance was 48%, and diagnostic was 23%, with only a tiny fraction (0.49%) having a fecal immunochemical test (FIT)-positive indication. The ADRs were 56% for surveillance, 49% for screening, and 38% for diagnostic examinations. Nonscreening examinations combined had an ADR of 50%. Over a range of indication scenarios (varying the fraction of screening, surveillance, and diagnostic examinations), the ADR for screening and overall ADRs remained quite similar.
Kaltenbach T, Gawron A, Meyer CS, et al. Adenoma detection rate (ADR) irrespective of indication is comparable to screening ADR: implications for quality monitoring. Clin Gastroenterol Hepatol 2021 Feb 18. (Epub ahead of print) ()