Final answer:
Incidence and prevalence are two important measures used when describing the magnitude of a public health problem.
Step-by-step explanation:
When measuring diseases that are difficult to pinpoint when an individual becomes a case, and for describing the magnitude of a public health problem, two specific statistical measures widely used in epidemiological investigations are incidence and prevalence.
Incidence is a measure of the number of new cases of a disease during a specific time period, while prevalence refers to the total number of both new and existing cases in a population over time.
These measures help understand risk factors, disease spread, and provide an indication of the overall health of the population.