Validation of the Prague C & M criteria for the endoscopic grading of Barrett's esophagus by gastroenterology trainees: A multicenter study

Background: The Prague C & M criteria, developed for the endoscopic grading of Barrett's esophagus (BE), (C = circumferential length, M = maximal length) were previously validated among a panel of 29 expert endoscopists with a special interest in BE. Its performance among gastroenterology trainees is unknown. Objective: To test interobserver agreement among gastroenterology trainees for the Prague C & M criteria, identification of the gastroesophageal junction (GEJ) and the diaphragmatic hiatus. Design: A prospective study. Setting: Two tertiary referral centers. Patients and Interventions: Standardized endoscopic videos were used. Main Outcome Measurements: Interobserver agreement. Results: Eighteen high-quality videos (normal esophagus, short and long lengths of BE, equally distributed) were independently evaluated by 18 gastroenterology trainees (year 1, n = 5; year 2, n = 6; year 3, n = 7) after administration of a formal teaching module by an expert endoscopist. Overall intraclass correlation coefficients for assessment of the C and M extent of the endoscopic BE segment above the GEJ were 0.94 (95% CI, 0.89-0.98) and 0.96 (95% CI, 0.94-0.98), respectively. The overall intraclass correlation coefficients for GEJ and diaphragmatic hiatus location recognition were 0.92 (0.86-0.96) and 0.90 (0.82-0.95), respectively. The year of training did not affect interobserver agreement. Limitations: The use of videos for endoscopic evaluation. Conclusion: After standardized teaching, the Prague C & M criteria have high overall validity among gastroenterology trainees irrespective of the level of training for endoscopic evaluation of visualized BE lengths as well as key endoscopic landmarks.