title: Intraobserver and interobserver consistency for grading esophagitis with narrow-band imaging.
abstract: BACKGROUND
  Narrow-band imaging (NBI) is a novel, noninvasive optical technique that adjusts reflected light to enhance the contrast between the esophageal mucosa and the gastric mucosa. Whether the use of this optical technique may increase consistency in describing the presence and severity of mucosal breaks remains elusive.
  
  
  OBJECTIVE
  We compared the intra- and interobserver variations in the endoscopic scoring of esophagitis by using conventional imaging with and without NBI.
  
  
  METHODS
  Cross-sectional study of consecutive patients with reflux.
  
  
  METHODS
  Single center in Taiwan.
  
  
  METHODS
  Endoscopic photographs of 230 patients with gastroesophageal reflux were obtained with both methods. Images were randomly displayed twice to 7 endoscopists, who independently scored each photograph by using the Los Angeles classification.
  
  
  METHODS
  We calculated intra- and interobserver kappa statistics to measure the consistency in interpretations.
  
  
  RESULTS
  With the addition of NBI, intraobserver reproducibility significantly improved with 3 of the 7 endoscopists. Interobserver reproducibility was more consistent with the combined approach than with conventional imaging alone, with an improved overall kappa value of 0.62 versus 0.45 (P < .05). Discordance between these methods was substantial in the grading of class A or B esophagitis.
  
  
  CONCLUSIONS
  A small sample of class D esophagitis might have produced insufficient statistical power in this category.
  
  
  CONCLUSIONS
  Intra- and interobserver reproducibilities in grading esophagitis could be improved when NBI was applied with conventional imaging. The benefit appeared to derive from better depictions of small erosive foci.
authors.affiliation: Department of Internal Medicine, College of Medicine, Institute of Preventive Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Yi-Chia
authors.initials: YC
authors.lastname: Lee
authors.forename: Jaw-Town
authors.initials: JT
authors.lastname: Lin
authors.forename: Han-Mo
authors.initials: HM
authors.lastname: Chiu
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Liao
authors.forename: Chien-Chuan
authors.initials: CC
authors.lastname: Chen
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Tu
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Tai
authors.forename: Tsung-Hsien
authors.initials: TH
authors.lastname: Chiang
authors.forename: Yueh-Hsia
authors.initials: YH
authors.lastname: Chiu
authors.forename: Ming-Shiang
authors.initials: MS
authors.lastname: Wu
authors.forename: Hsiu-Po
authors.initials: HP
authors.lastname: Wang
mesh_terms: D004941:Esophagitis / Q000145:classification / Q000473:pathology*; D004945:Esophagoscopy / Q000379:methods*; D004947:Esophagus / Q000473:pathology; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D009092:Mucous Membrane / Q000473:pathology; D015588:Observer Variation; D014741:Video Recording