Carbon 13 and carbon 14 are both urea breath tests, which are mainly used in clinical practice for the diagnosis and review of H. pylori infection, and both have a small difference in the accuracy rate during the test, which is more than 95%, making them a quick and non-invasive test. The two only differ in the test method, so patients are advised to consult with their doctors and make a choice based on their own situation. The following are the differences between the two: 1. Carbon 13: almost non-radioactive, can be applied to all people, the price of the test is relatively high; 2. Carbon 14: carbon 14 is cheaper and more sensitive, but the examination process is somewhat radioactive, may produce damage to the human body, not suitable for children, pregnant women, people preparing for pregnancy and lactating women. In addition, if there is recent use of anti-H. pylori drugs, or upper gastrointestinal bleeding, gastrectomy, etc., the test results may be affected, and you need to inform your doctor in advance. If the test result is positive, it indicates the presence of H. pylori infection, which should be treated with medication under the guidance of a doctor in a timely manner.