Clin Endosc.  2014 Jan;47(1):74-78.

Observer Variability in Gastric Neoplasm Assessment Using the Vessel Plus Surface Classification for Magnifying Endoscopy with Narrow Band Imaging

• Yoo CH
• Park MI
• Park SJ
• Moon W
• Kim HH
• Song JY
• Kim DH

Abstract

BACKGROUND/AIMS
Recent studies have demonstrated that magnifying endoscopy with narrow band imaging (ME-NBI) facilitates differentiation of early gastric cancer from gastric adenoma using vessel plus surface (VS) classification. This study estimated the interobserver and intraobserver agreement of endoscopists using the Yao VS classification system for the gastric mucosal surface.
METHODS
We retrospectively reviewed patients who underwent endoscopic submucosal dissection or endoscopic mucosal resection, and selected cases in which preoperative ME-NBI was conducted. Before testing endoscopists, a 20-minute training module was given. Static ME-NBI images (n=47 cases) were presented to seven endoscopists (two experts and five trainees) who were asked to assess the images in 20 seconds using the Yao VS classification system. After 2 weeks, the endoscopists were asked to analyze the images again. The kappa statistic was calculated for intraobserver and interobserver variability.
RESULTS
The mean kappa for intraobserver agreement was 0.69 (experts, 0.74; trainees, 0.64). The mean kappa for interobserver agreement was 0.42 (experts, 0.49; trainees, 0.40).
CONCLUSIONS
We obtained reliable results as assessed by observer variability, with only brief training on VS classification. The VS classification appears to provide an objective assessment of ME-NBI for trainees who are not familiar with ME-NBI.

Keyword

Endoscopy; Neoplasms; Stomach

MeSH Terms

Adenoma
Classification*
Endoscopy*
Humans
Narrow Band Imaging*
Observer Variation
Retrospective Studies
Stomach
Stomach Neoplasms*

Figure

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  Fig. 1 Magnifying endoscopy with narrow band imaging showing a typical finding of demarcation line and irregular microvascular pattern.

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  Fig. 2 Magnifying endoscopy with narrow band imaging showing a typical finding of regular microvascular and microsurface patterns

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