title: [Factors influencing the miss rate of polyps in a tandem colonoscopy study].
abstract: OBJECTIVE
  The miss rate of colon polyps and its related factors have not been clearly identified yet. This study aims to review the miss rate of polyps both on the patient-level and on the polyp-level and to analyze the factors affecting the miss rate such as those related to the endoscopist, procedure, patient, and polyp.
  
  
  METHODS
  From August 2011 to August 2013, patients who underwent elective second colonoscopy for resection of polyps, the sizes of which were not small enough to be resected by biopsy forceps alone at first colonoscopy, were enrolled retrospectively.
  
  
  RESULTS
  The miss rate on the patient-level was 59.2% (234/395) and on the polyp-level was 27.9% (578/2,068). There was no significant difference in the miss rate depending on the experience of the endoscopists or characteristics of the patients. In terms of the procedure, the miss rate was higher when the colonoscopy was performed in the afternoon (OR 1.632, p=0.046). It was found that the miss rate of polyps increased when the polyps were small (OR 4.595, p<0.001 in <5 mm/OR 3.447, p<0.001 in 5-10 mm), flat or sessile (OR 2.406, p<0.001 in flat/OR 1.768, p=0.002 in sessile), and located in the left colon (OR 1.391, p=0.007).
  
  
  CONCLUSIONS
  The experience of endoscopists did not have influence on the accuracy of polyp detection. However, the fatigue of endoscopists in the afternoon is considered to render polyp detection less accurate. Also, the large curves and folds of the sigmoid colon are regarded as a reason for the higher miss rate of polyps in the left colon.
authors: Department of Internal Medicine, Daegu Catholic University Medical Center, 33 Duryugongwon-ro 17-gil, Nam-gu, Daegu 705-718, Korea.
authors: Han Na
authors: HN
authors: Choi
authors: Hyun Hee
authors: HH
authors: Kim
authors: Jang Seok
authors: JS
authors: Oh
authors: Hee Sang
authors: HS
authors: Jang
authors: Hyun Sik
authors: HS
authors: Hwang
authors: Eun Young
authors: EY
authors: Kim
authors: Joong Goo
authors: JG
authors: Kwon
authors: Jin Tae
authors: JT
authors: Jung
mesh_terms: D000236:Adenoma / Q000175:diagnosis; D000368:Aged; D015992:Body Mass Index; D002983:Clinical Competence; D003110:Colonic Neoplasms / Q000175:diagnosis; D003111:Colonic Polyps / Q000175:diagnosis* / Q000473:pathology; D003113:Colonoscopy; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012189:Retrospective Studies; D013997:Time Factors