Water exchange minimizes magnitude and variations in maximum insertion pain among colonoscopists (and potentially enhances cost savings by promoting completion of unsedated colonoscopy)

1Digestive Endoscopy Unit, S. Barbara Hospital, Iglesias (CI), Italy; 2Digestive Endoscopy Unit, N. S. di Bonaria Hospital, San Gavino Monreale (VS), Italy; 3Department of Surgical Sciences, University of Cagliari (CA), Italy; 4Sepulveda Ambulatory Care Center, Veterans Affairs Greater Los Angeles Healthcare System, North Hills, CA, USA; 5David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA