title: Interobserver and intraobserver variation in endoscopic assessment of GERD using the "Los Angeles" classification.
abstract: BACKGROUND
  A new endoscopic classification of gastroesophageal reflux disease (GERD) has been proposed, and the term mucosal break has been introduced to describe mucosal damage. This new classification was evaluated by endoscopists with different levels of experience.
  
  
  METHODS
  Fifty endoscopic photographs for each of 20 randomly selected patients with GERD were assessed retrospectively by three groups of seven endoscopists classified by experience: group 1 (100 to 500 procedures), group 2 (500 to 3000), and group 3 (more than 3000). The new classification was modified by adding grade 0 to describe healed mucosal breaks, so that there were 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). Intraobserver variation in group 1 (kappa = 0.39, n = 7) was significantly different (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. Only experienced endoscopists should use the new classification for grading of GERD.
authors.affiliation: First Department of Internal Medicine, School of Medicine, Gunma University, Maebashi, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kusano
authors.forename: K
authors.initials: K
authors.lastname: Ino
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.forename: O
authors.initials: O
authors.lastname: Kawamura
authors.forename: M
authors.initials: M
authors.lastname: Toki
authors.forename: T
authors.initials: T
authors.lastname: Ohwada
authors.forename: K
authors.initials: K
authors.lastname: Kikuchi
authors.forename: T
authors.initials: T
authors.lastname: Shirota
authors.forename: M
authors.initials: M
authors.lastname: Kimura
authors.forename: M
authors.initials: M
authors.lastname: Miyazaki
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: S
authors.initials: S
authors.lastname: Igarashi
authors.forename: M
authors.initials: M
authors.lastname: Tomizawa
authors.forename: T
authors.initials: T
authors.lastname: Tamura
authors.forename: T
authors.initials: T
authors.lastname: Sekiguchi
authors.forename: M
authors.initials: M
authors.lastname: Mori
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology*; D005764:Gastroesophageal Reflux / Q000145:classification* / Q000473:pathology*; D005773:Gastroscopy / Q000379:methods / Q000592:standards*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011897:Random Allocation; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric