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Introduction to Epidemiology


Admission requirements



Epidemiology is the study of how often diseases occur in specific populations and why. Epidemiological research is the cornerstone of public health. Epidemiological evidence provides the foundation for public health measures, aimed at reducing disease burden in specific populations.

This course will introduce you to basic methods and study designs in epidemiology. The prevalence, incidence and main determinants of major communicable and non-communicable diseases will be addressed. By using examples, this course teaches different study designs used in epidemiology and public health research such as: case-control studies, cohort studies, randomized controlled trials and systematic reviews. Also, basic epidemiological and public health measures of associations will be discussed as well as potential biases and internal and external validity of epidemiological findings.

Course Objectives

At the end of this course, students will be able to:

  • Reproduce the prevalence, incidence and main determinants of common communicable and non-communicable diseases.

  • Explain basic frequency measures used in epidemiology, like the (cumulative) incidence and the prevalence, and basic measures of association like the risk ratio, rate ratio, and odds ratio.

  • Name and describe the study designs used in epidemiology and indicate the major advantages and disadvantages of the different study designs.

  • Be able to select the most suitable study design to address a specific research question and describe how to apply it.

  • Name and describe different forms of bias, like selection bias, information bias, and confounding.

  • Recognize and explain effect modification.

  • Explain the difference between internal and external validity.


Timetables for courses offered at Leiden University College in 2021-2022 will be published on this page of the e-Prospectus.

Mode of instruction

  • Lectures

  • Journal clubs

  • Case studies and exercises

  • Group assignment and presentations

Assessment Method

  • Individual assignments (written: ethics (15 %, due week 3); systematic review (15%, due week 5))

  • Group assignments: design a study (presentation and discussion (15%, due week 6); written report (15%; due week 7))

  • Final, written exam (open and multiple-choice questions (40%, due week 8))

Reading list

Webb P, Bain C. Essential Epidemiology: An Introduction for Students and Health Professionals. 2nd or 3rd edition. Cambridge: Cambridge University Press.


Courses offered at Leiden University College (LUC) are usually only open to LUC students and LUC exchange students. Leiden University students who participate in one of the university’s Honours tracks or programmes may register for one LUC course, if availability permits. Registration is coordinated by the Education Coordinator,


Dr Rutger A Middelburg,