"Correlation does not imply causation" is a common theme for much of the epidemiological literature. Epidemiology, literally meaning "the study of what is upon the people", is derived from Greek epi 'upon, among', demos 'people, district', and logos 'study, word, discourse', suggesting that it applies only to human populations. By contrast, other epidemiological fields have not required such rigorous reporting and are much less reliable as a result.. John Snow’s investigation of cholera is considered a model for epidemiologic field investigations because it included a: Comparison of a health outcome among exposed and unexposed groups. A. This activity will get students interested in infectious diseases by discussing and charting their own experiences. 0000003314 00000 n
In the middle of the 16th century, a doctor from Verona named Girolamo Fracastoro was the first to propose a theory that these very small, unseeable, particles that cause disease were alive. Descriptive observations pertain to the "who, what, where and when of health-related state occurrence". During a major cholera epidemic in 1854 London, he collected and mapped data on the locations (street addresses) where cholera deaths occurred.  He coined the terms endemic (for diseases usually found in some places but not in others) and epidemic (for diseases that are seen at some times but not others).. Other methods are being developed, but are not common practice yet. For instance, for an odds ratio of 1.5 and cases = controls, the table shown above would look like this: Cohort studies select subjects based on their exposure status.