Lecture 10 CONCLUSIONS Flashcards
Epidemiologists study the _____ and _____ of frequency of disease in humans
distribution and determinants
How is “disease frequency” expressed?
in either incidence rate or prevalence rate
What is incidence rate?
the number of new cases in a defined population at risk over a defined period of time
What is prevalence rate?
The number of existing cases in a defined population at a SINGLE POINT in time
Which rate is most useful in identifying causes of disease?
incidence rate
Descriptive epidemiology looks at…
distribution of disease based on the WHO, the WHEN, and the WHERE
The information on the distribution of a disease (the who, when and where) may lead to hypotheses about….
the determinants (cause) of the illness
Hypotheses generated through descriptive epidemiology can be tested through….
systemic epidemiological studies
What are intervention studies?
true experiments in which the subjects are assigned to either a test group or a control group
The most common and rigorous type of intervention study is the…….
randomized, double blind clinical trial (used to test new drug treatments or preventative measures)
In most cases, it would be unethical to investigate whether certain exposures cause a certain disease. So, what is the next best thing?
a cohort study
what is a cohort study?
subjects are questioned about their exposures and then tracked over time, comparing the exposed group with the unexposed group (to see whether the exposed group is more likely to develop the disease)
What is the 3rd major type of study?
case control study
Describe a case control study
BEGINS with cases of disease and questions them about what they’ve been exposed to, comparing their answers with those of the healthy control group
What factor limits the type of studies that epidemiologists can perform?
they study human populations
