Differences in colonoscopy performance among four endoscopy centers in Western Norway: Influence of case-mix

Abstract

Background and study aims

Unmodifiable patient factors such as age, sex, and indication (case-mix) may influence colonoscopy performance. In this study, we explored how case-mix affected polyp detection, cecal intubation, and pain on a center level.

Methods

A cross-sectional study was performed on data from four centers in Western Norway registered in the national endoscopy quality registry, Gastronet, in 2020 and 2021. We extracted demographics, indication, and the performance measures cecal intubation rate (CIR), proportion of at least one polyp ≥ 5 mm in size per colonoscopy (PDR-5), and pain. We also analyzed the explanatory variables bowel preparation, withdrawal time, and sedation/analgesia.

Results

First colonoscopies in 14,765 patients were included. Median age was 60 years (interquartile range 46–71) and 54% were women. Case-mix differed between centers and significantly influenced performance measures. Increased PDR-5 was associated with higher age and male sex (odds ratio [OR] 1.27, 95% confidence interval [CI] 1.18–1.37). The indication surveillance had the highest PDR-5 (44.9%, 95% CI 42.6–47.1) and inflammatory bowel disease the lowest (14.6%, 95% CI 12.3–16.8). CIR decreased with increasing age. Men had less pain (OR 0.33, 95% CI 0.27–0.39). Among indications, surveillance and IBD had higher CIRs and less pain. Performance measures differed among centers, even after adjustment for case-mix and other known explanatory variables such as sedation/analgesia and bowel preparation.

Conclusions

Case-mix influenced performance measures. Although we showed center differences in performance, other factors, such as individual endoscopist skills, probably influence performance measures. Our study demonstrates the importance of considering case-mix when assessing colonoscopy performance.

Keywords

Endoscopy Lower GI Tract - Polyps / adenomas / ... - Colorectal cancer - CRC screening - Quality and logistical aspects - Sedation and monitoring - Quality management

Publication History

Received: 02 October 2024

Accepted after revision: 14 February 2025

Article published online:
04 April 2025

• References

• 1 World Health Organization. Global Cancer Observatory. Cancer today. https://gco.iarc.fr/
• 2 Kaminski MF, Regula J, Kraszewska E. et al. Quality indicators for colonoscopy and the risk of interval cancer. N Engl J Med 2010; 362: 1795-1803
• 3 Corley DA, Jensen CD, Marks AR. et al. Adenoma detection rate and risk of colorectal cancer and death. N Engl J Med 2014; 370: 1298-1306
• 4 Kaminski MF, Thomas-Gibson S, Bugajski M. et al. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) quality improvement initiative. United European Gastroenterol J 2017; 5: 309-334
• 5 Gastronet. https://www.sthf.no/gastronet
• 6 Anderson JC, Butterly LF, Goodrich M. et al. Differences in detection rates of adenomas and serrated polyps in screening versus surveillance colonoscopies, based on the new hampshire colonoscopy registry. Clin Gastroenterol Hepatol 2013; 11: 1308-1312
• 7 Boroff ES, Disbrow M, Crowell MD. et al. Adenoma and polyp detection rates in colonoscopy according to indication. Gastroenterol Res Pract 2017; 2017
• 8 Mangas-Sanjuan C, Santana E, Cubiella J. et al. Variation in colonoscopy performance measures according to procedure indication. Clin Gastroenterol Hepatol 2020; 18: 1216-1223 e1212
• 9 Nass KJ, van der Vlugt M, Elfrink AKE. et al. Case-mix adjustment to compare colonoscopy performance between endoscopy centers: a nationwide registry study. Endoscopy 2022; 54: 455-462
• 10 Ladabaum U, Shepard J, Mannalithara A. Adenoma and serrated lesion detection by colonoscopy indication: The ADR-ESS (ADR Extended to all Screening/Surveillance) Score. Clin Gastroenterol Hepatol 2021; 19: 1873-1882
• 11 Pedersen L, Bernstein I, Lindorff-Larsen K. et al. Colonoscopy performance monitoring: do we need to adjust for case mix?. Scand J Gastroenterol 2023; 58: 937-944
• 12 Catlow J, Sharp L, Wagnild J. et al. Nationally automated colonoscopy performance feedback increases polyp detection: The NED APRIQOT randomized controlled trial. Clin Gastroenterol Hepatol 2024; 22: 1926-1936
• 13 Corley DA, Jensen CD, Marks AR. et al. Variation of adenoma prevalence by age, sex, race, and colon location in a large population: implications for screening and quality programs. Clin Gastroenterol Hepatol 2013; 11: 172-180
• 14 Seip B, Bretthauer M, Dahler S. et al. Patient satisfaction with on-demand sedation for outpatient colonoscopy. Endoscopy 2010; 42: 639-646
• 15 Holme O, Bretthauer M, de Lange T. et al. Risk stratification to predict pain during unsedated colonoscopy: results of a multicenter cohort study. Endoscopy 2013; 45: 691-696
• 16 Harris JK, Vader JP, Wietlisbach V. et al. Variations in colonoscopy practice in Europe: a multiCenter descriptive study (EPAGE). Scand J Gastroenterol 2007; 42: 126-134
• 17 Dossa F, Dube C, Tinmouth J. et al. Practice recommendations for the use of sedation in routine hospital-based colonoscopy. BMJ Open Gastroenterol 2020; 7
• 18 Calderwood AH, Jacobson BC. Comprehensive validation of the Boston Bowel Preparation Scale. Gastrointest Endosc 2010; 72: 686-692
• 19 Hoff G, Botteri E, Hoie O. et al. Polyp detection rates as quality indicator in clinical versus screening colonoscopy. Endosc Int Open 2019; 7: E195-E202
• 20 Gastronet. Gastronet, articles of association. https://www.sthf.no/4aade2/siteassets/seksjon/forskning/gastronet/vedtekter-for-gastronet.pdf
• 21 Bhangu A, Bowley DM, Horner R. et al. Volume and accreditation, but not specialty, affect quality standards in colonoscopy. Br J Surg 2012; 99: 1436-1444
• 22 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; 19: 1883-1889 e1881
• 23 Shah SC, Itzkowitz SH. Colorectal cancer in inflammatory bowel disease: mechanisms and management. Gastroenterology 2022; 162: 715-730 e713
• 24 Axelrad J, Olen O, Soderling J. et al. Inflammatory bowel disease and risk of colorectal polyps: A nationwide population-based cohort study from Sweden. J Crohns Colitis 2023; 17: 1395-1409
• 25 Hoff G, Holme O, Bretthauer M. et al. Cecum intubation rate as quality indicator in clinical versus screening colonoscopy. Endosc Int Open 2017; 5: E489-E495
• 26 Hoff G, de Lange T, Bretthauer M. et al. Registration bias in a clinical quality register. Endosc Int Open 2019; 7: E90-E98
• 27 Sedgwick P, Greenwood N. Understanding the Hawthorne effect. BMJ 2015; 351: h4672