Association of endoscopist colonoscopy quality measures with follow-up colonoscopy outcomes after positive stool tests (mt-sDNA or FIT): Retrospective cross-sectional analysis of data from the New Hampshire Colonoscopy Registry.

BACKGROUND Negative colonoscopies following positive stool tests could result from stool test characteristics or from the quality of endoscopist performance. We used New Hampshire Colonoscopy Registry data to examine the association between endoscopist detection rates and polyp yield in colonoscopies performed for positive FIT or mt-sDNA tests to evaluate the degree to which positive stool tests followed by negative colonoscopy ('false positives') vary with endoscopist quality. Additionally, we investigated the frequency of significant polyps in the sub-group of highest quality colonoscopies following positive stool tests. METHODS We compared the frequencies of negative colonoscopies, and of specific polyps following positive stool tests across quartiles of endoscopist adenoma detection rate (ADR) and clinically significant serrated polyp detection rate (CSSDR). RESULTS Our sample included 864 mt-sDNA+ and 497 FIT+ patients. We found a significantly lower frequency of negative colonoscopies following positive stool tests among endoscopists with higher ADR and CSSDR, particularly in the two highest quartiles. Additionally, detection of any adenoma after a positive stool test for endoscopists in the 4th ADR quartile was 63.3% (FIT+) and 62.8% (mt-sDNA+). Among endoscopists in the 4th CSSDR quartile, SSLs were found in 29.2% of exams following a positive mt-sDNA, and in 13.5% following FIT+ exams. CONCLUSIONS The frequency of negative colonoscopies after positive stool tests was significantly higher in exams performed by endoscopists with low ADR and CSSDR. Our results also suggest a benchmark target of at least 40% for ADR in patients with mt-sDNA+ or FIT+ tests, and 20% for SSLs in mt-sDNA+ patients.