title: The Relationship Between Colonoscopy Procedure Order and Adenoma Detection Rates: A Prospective Study.
abstract: OBJECTIVE
  The aim of this study was to prospectively assess the effects of the order of colonoscopic procedures and other possible factors on the adenoma detection rate (ADR).
  
  
  BACKGROUND
  There have been conflicting studies regarding the timing or order of a colonoscopy and its ability to detect adenomas.
  
  
  METHODS
  Between March 2011 and July 2011, consecutive colonoscopies were prospectively performed by 7 board-certified staff endoscopists at the Seoul National University Hospital Healthcare System Gangnam Center. The primary outcome was the overall ADR according to the procedure order of the colonoscopies, and the secondary outcome was the identification of other possible factors influencing the ADR.
  
  
  RESULTS
  A total of 1908 colonoscopies were analyzed. The detection rate was 56.5% for all polyps and 37.3% for adenomas. The ADR increased as the performance order of the colonoscopy increased and was highest for the third procedure (43.4%). However, the ADR of the remaining procedures, including later procedures, was similar throughout the workday. In the multivariable analysis, the ADR was significantly associated with older age, male sex, high body mass index, personal history of colorectal polyps, long withdrawal time, and an experienced endoscopist. However, the colonoscopy procedure order was not significantly associated with the ADR.
  
  
  CONCLUSIONS
  The ADR was stable according to the procedure order for the later procedures of the workday in a setting of moderate daily procedure volumes. The withdrawal time and experience level of the endoscopist were more important than the procedure order in detecting adenomas by colonoscopy.
authors.affiliation: *Department of Internal Medicine, Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center †Department of Preventive Medicine, Ulsan University College of Medicine ‡Department of Internal Medicine, Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Hae Yeon
authors.initials: HY
authors.lastname: Kang
authors.forename: Donghee
authors.initials: D
authors.lastname: Kim
authors.forename: Hwa Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Seung Joo
authors.initials: SJ
authors.lastname: Kang
authors.forename: Goh Eun
authors.initials: GE
authors.lastname: Chung
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Song
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Yang
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Park
authors.forename: Jeong Yoon
authors.initials: JY
authors.lastname: Yim
authors.forename: Seon Hee
authors.initials: SH
authors.lastname: Lim
authors.forename: Joo Sung
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000473:pathology; D000328:Adult; D000367:Age Factors; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003111:Colonic Polyps / Q000175:diagnosis* / Q000473:pathology; D003113:Colonoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010820:Physicians / Q000592:standards; D011446:Prospective Studies; D012737:Sex Factors; D013997:Time Factors