Final answer:
The description refers to one of Hill's criteria in epidemiology, where the causal factor must precede the disease in time.
Step-by-step explanation:
The description given in the question is referring to one of the criteria known as the temporal relationship in the field of epidemiology. According to this criteria, the causal factor, such as a pathogen, must precede the onset of the disease in time. This means that the causal factor must be present before the disease occurs. It is one of the criteria proposed by the epidemiologist Hill to establish a causal relationship between an exposure and a disease.