Summary Online Epidemiology Course
Research Designs
Epidemiology is a strong increase in the
prevalence of a certain disease and is not
limited to infectious diseases.
Epidemiology is the research of a disease or
health in people, while epidemiology is the
methodology of epidemiological research.
Descriptive epidemiology: Frequencies of
disease of health states in populations
For example: What is the proportion of yearly
lung cancer cases in the Dutch adult
population?
Analytical epidemiology: It is about relationships, causes, diagnostics or course of diseases. For
example: Is smoking a cause of lung cancer?
In analytical epidemiology there are determinants (the possible cause; independent variable) and the
outcome (dependent variable).
Epidemiological studies are most interested in relationships between determinants and outcomes
(cause and effect relationships).
There are a lot of factors that can influence the outcome that was measured, that were measured or
weren't measured. Therefore, it can become difficult to measure the effect of a certain determinant on
a outcome.
Experimental designs (Trials; Randomized Trials)
In experimental research, the study of the participants is manipulated with the aim of examining
whether the manipulation has any effect. The participants are assigned to a category of the
determinant, and the researcher chooses what the category of the determinant is.
In experimental studies participants are allocated to a determinant (intervention) and can be extended
to comparison of more than 2 groups.
For example: Exercise therapie vs massage vs placebo
Experimental trials can be divided into:
• Pragmatic trials
• Explanatory trials
In pragmatic trials the degree of beneficial effect in "real" clinical practice are measured. So the
question that is asked: Which treatment is the best for my patient? (not important why the
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Research Designs
Epidemiology is a strong increase in the
prevalence of a certain disease and is not
limited to infectious diseases.
Epidemiology is the research of a disease or
health in people, while epidemiology is the
methodology of epidemiological research.
Descriptive epidemiology: Frequencies of
disease of health states in populations
For example: What is the proportion of yearly
lung cancer cases in the Dutch adult
population?
Analytical epidemiology: It is about relationships, causes, diagnostics or course of diseases. For
example: Is smoking a cause of lung cancer?
In analytical epidemiology there are determinants (the possible cause; independent variable) and the
outcome (dependent variable).
Epidemiological studies are most interested in relationships between determinants and outcomes
(cause and effect relationships).
There are a lot of factors that can influence the outcome that was measured, that were measured or
weren't measured. Therefore, it can become difficult to measure the effect of a certain determinant on
a outcome.
Experimental designs (Trials; Randomized Trials)
In experimental research, the study of the participants is manipulated with the aim of examining
whether the manipulation has any effect. The participants are assigned to a category of the
determinant, and the researcher chooses what the category of the determinant is.
In experimental studies participants are allocated to a determinant (intervention) and can be extended
to comparison of more than 2 groups.
For example: Exercise therapie vs massage vs placebo
Experimental trials can be divided into:
• Pragmatic trials
• Explanatory trials
In pragmatic trials the degree of beneficial effect in "real" clinical practice are measured. So the
question that is asked: Which treatment is the best for my patient? (not important why the
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