Epidemiology

3. Types of epidemiological studies

3.1 Descriptive studies (continued)

Different types of descriptive studies

• Case reports or a case series:

  These are the clinical descriptions of one or more cases.

  (a) Example of a descriptive study that is a case series

• Ecological studies:

  These examine how frequently a disease occurs in relation to the amount of exposure to a specific factor (consumption of a food or drugs, exposure to a chemical substance, etc.) in a group of individuals

  (b) Example of a descriptive study that is an ecological study

• Longitudinal studies:

  These examine the frequency of a disease in a population.

  (c) Example of a descriptive study that is a cross-sectionnal study