Interobserver and intraobserver variation in endoscopic assessment of GERDusing the "Los Angeles" classification

Background: A new endoscopic classification of gastroesophageal reflux dise ase (GERD) has been proposed, and the Perm mucosal break has been introduce d to describe mucosal damage. This new classification was evaluated by endo scopists with different levels of experience. Methods: Fifty endoscopic photographs for each of 20 randomly selected pati ents with GERD were assessed retrospectively by three groups of seven endos copists classified by experience: group 1 (100 to 500 procedures), group 2 (500 to 3000), and group 3 (more than 3000). The new classification was mod ified by adding grade 0 to describe healed mucosal breaks, so that there we re five grades. All photographs were assessed twice at an interval of more than 1 week, and kappa statistics were used to determine observer variation . Results: Interobserver variation within group 3 (kappa = 0.39, n = 21) and between groups 3 and 2 (kappa = 0.36, n = 49) was significantly different ( p < 0.01) from that between groups 3 and 1 (kappa = 0.26, n = 49). Intraobs erver variation in group 1 (kappa = 0.39, n = 7) was significantly differen t (p < 0.01) from that in group 2 (kappa = 0.51, n = 7) and group 3 (kappa = 0.54, n = 7). Conclusions Observer variation depends on level of endoscopic experience. O nly experienced endoscopists should use the new classification for grading of GERD.