When explaining the term population at risk in accordance with epidemiology it can be defined as the group of people, healthy or sick, who would be counted as cases if they had the disease being studied. So, in other words, a population at risk is those being studied for a particular reason. One example of a population at risk would be a general practitioner conducting a study on the amount of people that believed they contracted the flu from self-diagnosing from information they received off of Web MD. The population at risk would be those patients already on his client list and those who were using walk-in services if provided. Just like a ratio the population at risks denominators is the total of people while the numerators are the known
