Effect of Non-invasive Neuromodulation on the Quality of Intestinal Cleansing

Inclusion Criteria: * 18 to 78 years of age, male or female; * Intended to undergo diagnostic, screening, or surveillance colonoscopy; * Signed written informed consent. Exclusion Criteria: * Severe cardiac, cerebral, pulmonary, or renal complications or a history of acute cardiac infarction within six months; * High risk factors for bowel preparation such as history of colon surgery, BMI ≥ 28, inflammatory bowel disease, constipation (less than 3 bowel movements in the last week, and with straining to defecate, with hard stools and small amount of stools) or bowel obstruction; * High suspicion of colorectal cancer by auxiliary examination or early warning signs and symptoms of colorectal cancer: blood in stool, black stool, unexplained anemia, significant weight loss, abdominal mass and positive rectal fingerprinting; * The presence of surgical incisions or scars in the area where the electrostimulation treatment tablets are pasted, or near the ST36 acupoints on both legs; * Are participating in other clinical observation trials or have participated in other clinical trials within 30 days.