View all slides | Contents of this slide

Lecture Notes

We'll spend the first few slides on this lesson going over general disease-related terms to make sure we're all on the same page when discussing common chronic diseases throughout the remainder of the semester, and so to begin, when we talk about how common a particular disease is, we often use terms like prevalence and incidence. Prevalence is simply the number of existing cases or the total number of people in a particular population who have a disease at a specific point in time. So for example, the number of people who currently have diabetes in the United States would be an example of a prevalence rate. Incidence is the number of new cases of a disease for a specific time period. So for example, you might see the number of new cases of diabetes this year. And so what you'll notice here is that prevalence is always going to be higher than the incidence of a disease because prevalence includes those new cases of the disease. Two other terms that we use very often are mortality, or the rate of death, or total number of deaths in a given time period, and morbidity, which is the state of disease or illness.