Bowel pacing (specific location and parameters) and ST36 acupoint stimulation (specific location and intensity) were used the day before the examination; 2L of PEG was taken the night before the examination and on the day of the examination, and 30 ml of simethicone was taken orally immediately after all of the 4L of PEG had been taken. Colonoscopy was completed within 2-6 hours after bowel preparation was completed.

Sham acupoint bowel pacing and sham ST36 acupoint stimulation were used the day before the examination (electrode pads were offset and current switch was not turned on; 2L of PEG was taken the night before and on the day of the examination, respectively, and 30 ml of simethicone was taken orally immediately after all of the 4L of PEG had been taken. Colonoscopy was completed within 2-6 hours after bowel preparation was completed.

Only conventional treatment was used, with 2 portions of 2000 ml PEG taken with fasting starting at 19:00 pm the night before the examination and required to be taken within 2 hours. On the day of the examination, 2 doses of 2000 ml of PEG were taken orally starting 3-5 hours before the colonoscopy procedure, which was required to be completed within 2 hours, and 30 ml of simethicone was taken orally as soon as the subject had finished taking the laxative, and all bowel preparations had to be completed more than 2 hours and less than 6 hours before the colonoscopy procedure, and if the time limit was exceeded the subject was excluded from the study.

The day before the examination began a real stimulation treatment, namely, intestinal pacing (① location: positive pole placed on the navel (the line between the raphe and navel) 1 to 2 cm, the negative pole in the raphe and the navel line at the midpoint of the right 4 to 10 cm; ② parameters: the intestinal frequency: 2.4-3.7 cpm, the first time the frequency of use of 3.0 cpm, treatment of the base wave intensity of 0-15 gears, the first time to use the intestinal treatment intensity of 10 gears) , acupoint stimulation (① location: treatment sheet attached to both legs ST36 acupoints, i.e., four transverse fingers below the eye of the outer knee, 4 transverse fingers next to the tibia; ② parameters: the first use of acupoint intensity 30%, to the patient's self-conscious stimulation points have a slight pinprick sensation, lifting sensation, warm sensation is appropriate).

Using the Boston Bowel Preparation Scale(BBPS)