A positive C14 breath test is classified into 4 levels, the higher the level, the more serious the disease is, and is used to check for H. pylori, not only to determine whether the stomach is infected, but also to determine the degree of infection, with high accuracy and without causing discomfort to the patient. The test is positive and negative, and a positive test indicates that the infection is present, but the degree of infection is directly related to the plus sign. When the level of infection is within 100 DPM, it is a grade 1, which is normal; when the level of infection is between 100 and 500 DPM, it is a grade 2, which will show (+), and most of these people will have some symptoms. When the level of infection is between 500-1400 DPM, it is grade 3, which indicates that the patient’s condition is more serious and needs to be treated with medication as soon as possible. grade 4 is between 1500-2500 DPM, which is a severe infection, and this grade is higher, and most of these people will have some stomach diseases and need timely treatment.