According to Baidu's health display, you can't scrape the health certificate several times in the anus, which may affect the results of stool examination. First of all, the anus has always been in a relatively closed environment, which is easy to breed bacteria. As long as the anus is scraped a few times during stool examination, these bacteria will enter the sample, which will affect the correctness of stool examination results. Secondly, scraping the anus several times during stool examination will mix skin and mucosal cells near the anus in the samples submitted for inspection, which will have a great influence on the results of stool examination and easily mislead doctors to judge the condition. Therefore, it is necessary and necessary to carefully observe the precautions when checking the health certificate.