The cecal intubation rate (CIR) is a widely accepted key performance indicator (KPI) in colonoscopy but lacks a universal calculation method. We aimed to assess whether differences in CIR calculation methods could have an impact on perceived trainee outcomes.

A systematic review of CIR calculation methods was conducted on major societal guidelines (United Kingdom, European Society of Gastrointestinal Endoscopy [ESGE] and American Society for Gastrointestinal Endoscopy [ASGE]) and trainee-inclusive studies. Trainees awarded colonoscopy certification between June 2011 and 2016 were identified from the United Kingdom e-portfolio and selected as a validation cohort. For each trainee, both the crude and unassisted CIR were calculated for 50 post-certification procedures using definitions from the 3 international guidelines. The resulting CIRs, and the proportions of endoscopists failing to meet the minimum standard of CIR ≥90%, were then compared across these definitions.

Across the 3 guidelines and 37 eligible studies identified, differences in CIR calculation methodology were demonstrated. These related to adjustment criteria (18 studies) and whether unassisted CIR was stipulated (18 studies). In the validation cohort of 733 trainees (36,650 procedures), the median crude CIR ranged from 96% (ESGE) to 98% (ASGE) (P < .001) and whether unassisted CIR was specified (ESGE, 94%; ASGE, 96%; P < .001). The proportion of trainees failing to achieve CIR ≥90% varied significantly across the different definitions, from 4.9% for the crude ASGE definition to 18.6% for the unassisted ESGE definition (P < .001).

CIR calculation methods vary among guidelines and research studies; this has an impact on trainee performance measures. With CIR used as an example, this study highlights the need for standardized definitions and calculations of KPIs in endoscopy.