Population-based studies aim to answer research questions for defined populations. Answers should be generalizable to the whole population addressed in the study hypothesis, not only to the individuals included in the study. This point addresses the point of external validity of the findings. Therefore, the valid definition as well as the reliable and valid identification of populations in which research questions for specific populations can be studied is the most important issue in population-based studies.
Population-based studies may include a variety of study types. They may include case–control studies, cross-sectional studies, twin studies, or prospective and retrospective cohort studies. The important issue is the selection of the individuals that are included into the study – they should be representative of all individuals in the a priori defined specific population.
For example, in a population-based prospective cohort study, in which an association between a...
References and Readings
- Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern epidemiology (3rd ed.). Philadelphia: Lippincott Williams & Wilkins.Google Scholar