title: Comparison of detection and miss rates of narrow band imaging, flexible spectral imaging chromoendoscopy and white light at screening colonoscopy: a randomised controlled back-to-back study.
abstract: OBJECTIVE
  Virtual chromoendoscopy (CE) is expected to enhance adenoma yield and reduce variation in performance between colonoscopists. This study aimed to compare the efficacy of narrow band imaging (NBI), flexible spectral imaging CE (FICE) and white light (WL) colonoscopy and their impact for less experienced endoscopists.
  
  
  METHODS
  We performed a randomised tandem colonoscopy trial controlling for withdrawal time and bowel preparation. Average-risk adults undergoing screening colonoscopy were enrolled and randomly assigned to first withdrawal with one of the three imaging modalities (NBI (NBI-WL group), FICE (FICE-WL group) and WL (WL-WL group)). Eight colonoscopists were categorised into expert and non-expert subgroups.
  
  
  RESULTS
  1650 subjects (mean age 51.4 years, 63.9% men) were included (550 in each group). Compared with WL, neither NBI nor FICE increased the mean number of adenomas detected per patient (0.37 vs 0.35 and 0.36; p=0.591) or the percentage of patients with adenoma (25.3% vs 24.5% and 23.6%; p=0.753). For all three modalities, expert subgroups had higher yields of adenomas than non-expert subgroups. Learning curves were observed only for non-expert subgroups with all three modalities. The percentage of missed adenomas did not differ between the three groups (20.8% by WL vs 22.9% by NBI and 26.0% by FICE, p=0.300) and was not affected by endoscopists' expertise.
  
  
  CONCLUSIONS
  Neither NBI nor FICE improved adenoma detection or miss rates, with no difference in diagnostic efficacy between the two systems. Virtual CE had no additional benefits over WL for non-experts.
  
  
  BACKGROUND
  KCT0000570.
authors.affiliation: Department of Internal Medicine, Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, , Seoul, Republic of Korea.
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Chung
authors.forename: Donghee
authors.initials: D
authors.lastname: Kim
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Song
authors.forename: Hae Yeon
authors.initials: HY
authors.lastname: Kang
authors.forename: Goh Eun
authors.initials: GE
authors.lastname: Chung
authors.forename: Jeongmin
authors.initials: J
authors.lastname: Choi
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Park
authors.forename: Joo Sung
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000368:Aged; D003110:Colonic Neoplasms / Q000175:diagnosis; D003113:Colonoscopy / Q000379:methods* / Q000523:psychology; D003951:Diagnostic Errors / Q000523:psychology / Q000706:statistics & numerical data*; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D057194:Intention to Treat Analysis; D059032:Learning Curve; D008027:Light; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D062048:Narrow Band Imaging / Q000523:psychology; D011446:Prospective Studies
keywords: Adenoma; Colonoscopy; Screening