Epidemiology is the study of how often diseases occur in different groups of people and why. This involves not just measuring disease frequency (incidence/prevalence), but also understanding patterns and causes.
To conduct an epidemiologic study, key information needed includes:
- Population data (age, sex, location)
- Disease data (number of cases, how it's diagnosed)
- Time and place of occurrence (to track trends and outbreaks)
- Risk factors (e.g. behavior, environment, genetics)
- Comparison groups (to identify associations or causes)