title: Water infusion versus air insufflation for colonoscopy: a meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  The aim of this meta-analysis was to determine whether water infusion colonoscopy (WIC) is a more effective diagnostic tool than standard air insufflation colonoscopy (AIC).
  
  
  METHODS
  All articles pertinent to a comparison of water-related methods and air insufflation to facilitate insertion of the colonoscope were retrieved from PubMed, Web of Science, Embase, and Cochrane databases. Pooling results were derived by using the Review Manager Software. Outcomes were assessed using the weighted mean difference (MD) with 95 % confidence intervals (CI) for continuous variables and the odds ratios (OR) with 95 % CI for dichotomous variables.
  
  
  RESULTS
  Eighteen studies involving 2,797 patients were included. WIC was associated with a significantly higher cecal intubation rate than AIC (OR = 1.90; 95 % CI 1.21-2.99; p = 0.005). The intubation time was similar for the two types of colonoscopy, but in WIC there was a significantly lower visual analog scale score for abdominal pain than in AIC (MD = -1.30; 95 % CI -2.03 to -0.58; p < 0.001) without sacrificing the polyp detection rate (OR = 1.17; 95 % CI 0.78-1.77; p = 0.44). Statistically, the patient's willingness to repeat colonoscopy was significantly greater for WIC than for AIC (OR = 1.74; 95 % CI 1.14-2.67; p < 0.01). Furthermore, in the subgroup for trainees, the WIC group achieved a higher cecal intubation rate (OR = 1.83; 95 % CI 1.15-2.93; p = 0.01) and a shorter intubation time (MD = -1.72 min; 95 % CI -3.34 to -0.11; p = 0.04) than the AIC group.
  
  
  CONCLUSIONS
  In contrast to AIC, WIC improved cecal intubation, alleviated abdominal pain, and increased patients' willingness to repeat the procedure.
authors: Department of Gastroenterology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People's Republic of China.
authors: D
authors: D
authors: Hu
authors: Y
authors: Y
authors: Xu
authors: Y
authors: Y
authors: Sun
authors: Q
authors: Q
authors: Zhu
mesh_terms: D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D007327:Insufflation / Q000009:adverse effects / Q000379:methods*; D008297:Male; D016017:Odds Ratio; D010147:Pain Measurement; D057240:Patient Preference; D017060:Patient Satisfaction / Q000706:statistics & numerical data; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D014867:Water
chemical_list: D014867:Water
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