title: Enhanced instructions improve the quality of bowel preparation for colonoscopy: a meta-analysis of randomized controlled trials.
abstract: OBJECTIVE
  The success of a colonoscopy is highly dependent on the quality of bowel preparation (BP). Many patients have poor BP due to non-compliance with regular instructions. Reports concerning the effects of enhanced instructions on BP quality are inconsistent. The aim of this meta-analysis was to compare BP quality between patients receiving enhanced instructions in addition to regular instructions and those who received regular instructions only.
  
  
  METHODS
  MEDLINE, EMBASE, Web of Science, and the Cochrane Library were searched to identify relevant studies published for August 2015. The quality of BP (adequate/inadequate), adenoma detection rate, polyp detection rate, willingness to repeat preparation, and adverse events were estimated by using odds ratios (OR) and 95% confidence intervals (CI) with random effects models.
  
  
  RESULTS
  Eight randomized controlled trials (n = 3795) were included. Patients who received enhanced instructions showed significantly better BP quality than those receiving only regular instructions (OR, 2.35; 95% CI, 1.65-3.35; P < .001). Subgroup analysis showed that the beneficial effects of enhanced instructions on BP quality were consistent among patients receiving different purgative types, administration methods, or diet restriction (all P < .05). Patients in the enhanced instructions group showed more willingness to repeat the preparation (OR, 1.91; 95% CI, 1.20-3.04; P = .006).
  
  
  CONCLUSIONS
  Enhanced instructions significantly improved the quality of BP and willingness to repeat the preparation in patients undergoing colonoscopy. Factors related to patient instructions appear to be as important as the preparation method itself in improving BP quality.
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Guo
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Radiotherapy, Xijing Hospital, Fourth Military Medical University, Xian, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Division of Gastroenterology, Department of Medicine, Sepulveda Ambulatory Care Center, Veterans Affairs Greater Los Angeles Healthcare System, 16111 Plummer Street, North Hills, California, USA; David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, California, USA.
authors.forename: Felix
authors.initials: F
authors.lastname: Leung
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Luo
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Kang
authors.affiliation: Department of Nursing, Fourth Military Medical University, Xian, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Jia
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Shengye
authors.initials: S
authors.lastname: Yang
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Tao
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Yanglin
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xian, China.
authors.forename: Xuegang
authors.initials: X
authors.lastname: Guo
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging*; D001205:Ascorbic Acid / Q000008:administration & dosage; D002400:Cathartics / Q000008:administration & dosage* / Q000009:adverse effects; D002432:Cecum; D003111:Colonic Polyps / Q000000981:diagnostic imaging; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D004032:Diet; D055088:Early Detection of Cancer; D006801:Humans; D007441:Intubation, Gastrointestinal; D010349:Patient Compliance; D010353:Patient Education as Topic / Q000379:methods*; D011092:Polyethylene Glycols / Q000008:administration & dosage; D016032:Randomized Controlled Trials as Topic
chemical_list: D002400:Cathartics; D011092:Polyethylene Glycols; D001205:Ascorbic Acid