A H. pylori test result of 42 dpm/mmol is indicative of a negative carbon 14 test for H. pylori, representing no infection. Carbon 14 breath test is one of the widely used methods for detecting H. pylori infection, and the normal value of carbon 14 test is 0-100 dpm/mmol, indicating negative for H. pylori. If it exceeds 100dpm/mmol, it indicates H. pylori positive. There are various methods of testing for H. pylori, including carbon 14 and carbon 13, each of which has a different normal value and therefore a different value in severe cases. The normal value for the carbon 13 test is 0-4 dpm/mmol, which suggests H. pylori negativity. If it is more than 4dpm/mmol, it represents H. pylori positive. If the test result of H. pylori is abnormal, it is recommended to go to a regular hospital in time and under the guidance of the doctor to carry out sterilization treatment in order to reduce the adverse effects of the disease.