Question

Explain the term “population at risk” and provide at least two relevant examples as seen in the practice of modern epidemiology.

Answer 1

Ans: An important characteristic of epidemiology its ability to measure disease outcomes as they relate to a population at risk. The population at risk is simply the number of individuals (healthy or sick) that have not developed the disease or illness of interest but have a great probability of developing the disease or illness due to various reasons (Barratt et. al., 2018). In most cases, it is a specific group of people in a population (such as unimmunized individuals, children, men, or women) but it could also be an entire population (such as a city, county, state, or even the nation). It can also include specialized populations such as injury or illness associated with a certain occupation or sport. When calculating a rate (such as the incidence or prevalence rates), the denominator represents the specific population at risk (Friis & Sellers, 2014). When determining the most accurate denominator for these rates, it is important to only include individuals who could potentially develop the disease or illness of interest and not those who could not or never develop it. For instance, women should not be included in any rates associated with prostate diseases since only men develop these. The most relevant examples concerning the use of population at risk are seen the prevalence or incidence rates. Incidence is the measure of new cases for a disease or illness that develop in the at-risk population and prevalence is the number of existing cases within a specified population. Both prevalence and incidence are useful in quantifying the burden of disease within a population at risk which is useful for planning and executing the necessary health services that may be required for a specific area or population (Barratt et. al., 2018).