Current Status of Bowel Preparation for Colonoscopy in Japan: A Web-Based Survey of Endoscopists (PRESS Survey).

The increasing number of patients with colorectal cancer underscores the importance of colonoscopy. Adequate bowel preparation is essential to ensure the quality and safety of colonoscopic examinations; however, data on the current practices in Japan remain limited. This study aimed to clarify the current status of bowel preparation, use of bowel-cleansing agents, and associated challenges among physicians performing colonoscopies. In March 2026, we conducted a nationwide web-based cross-sectional survey of physicians performing colonoscopies in Japan. The survey assessed bowel preparation practices, use of bowel-cleansing agents, constipation, and renal function before colonoscopy. Responses were obtained from 300 physicians who performed at least 10 colonoscopies per month. Low-volume polyethylene glycol (PEG) plus ascorbate preparations were the most commonly used bowel-cleansing agents, followed by high-volume PEG preparations and magnesium-based agents. Cleansing efficacy and safety were the most highly valued characteristics of bowel-cleansing agents. 64.7% of physicians reported that the perceived frequency of inadequate bowel preparation was >10% among their patients. Although 64.3% of the physicians reported always assessing constipation, only 32.7% reported always evaluating renal function before colonoscopy. Compared with hospital-based physicians, those working in clinics reported a significantly lower proportion of inadequate bowel preparation, but a significantly lower rate of renal function assessment. Although cleansing efficacy and safety are prioritized in bowel preparation for colonoscopy in Japan, physicians perceived inadequate bowel preparation to occur in a substantial proportion of patients. Thus, further optimization of bowel preparation strategies and more consistent assessment of renal function before colonoscopy are needed. University Hospital Medical Information Network (UMIN000060808).