title: Quantitative assessment of the effect of position changes during colonoscopy withdrawal.
abstract: OBJECTIVE
  Although trials assessing the effectiveness of position changes during colonoscopy withdrawal have been reported, there has been no agreement whether such position changes actually improve the polyp detection rate (PDR) or adenoma detection rate (ADR). This article aimed to address this issue by performing a systematic review.
  
  
  METHODS
  Relevant studies from databases including PubMed, EMBASE and the Cochrane Library and Science Citation Index were retrieved. Two reviewers independently identified potentially relevant studies. Outcome measures were PDR, ADR and bowel distention.
  
  
  RESULTS
  Eight studies were included, of which seven were randomized controlled trials (RCTs). A non-randomized controlled trial and all four cross-over RCTs reported significant improvement in PDR, ADR and bowel distention with position change during colonoscopic withdrawal, while three parallel-group RCTs did not confirm its effectiveness.
  
  
  CONCLUSIONS
  The conflicting results of high-quality trials indicate that the effectiveness of position change during colonoscopy withdrawal on PDR, ADR and bowel distension is uncertain. Thus, position change during colonoscopy withdrawal should not be routinely applied until future studies demonstrate its efficacy.
authors.affiliation: Student Brigade, Second Military Medical University, Shanghai, China.|Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Sheng Bing
authors.initials: SB
authors.lastname: Zhao
authors.affiliation: Education Office, Graduate School, Second Military Medical University, Shanghai, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wan
authors.affiliation: Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Hong Yu
authors.initials: HY
authors.lastname: Fu
authors.affiliation: Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu Province, China.
authors.forename: Zhen Xiu
authors.initials: ZX
authors.lastname: Liu
authors.affiliation: Student Brigade, Second Military Medical University, Shanghai, China.
authors.forename: Qing Song
authors.initials: QS
authors.lastname: Wang
authors.affiliation: Student Brigade, Second Military Medical University, Shanghai, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Ji
authors.affiliation: Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Zhao Shen
authors.initials: ZS
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Bai
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D003111:Colonic Polyps / Q000175:diagnosis; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D020878:Device Removal; D004106:Dilatation; D006801:Humans; D056888:Patient Positioning / Q000379:methods*; D012107:Research Design
keywords: adenoma; colonoscopy withdrawal; polyps; position change; systematic review