EPI 712 Midterm study guide
James Lind
One of the first clinical trials in humans , trial was focused on
preventing scurvy and discovered citrus fruit and vitamin c as
the solution
William Farr
Developed census data using marriages, deaths, and births. Used
a numerator and census data in the denominator
John Snow
The father of epidemiology because he created and rigorously
tested hypotheses. Discovered that cholera must be introduced to
the alimentary canal and accidentally swallowed. The increase
in morbid materials or cholera poison must take place in the
stomach and bowels
Strength of association
The larger the association, the more likely the exposure is to
cause the disease
Consistency
Association is observed repeatedly in different persons, places,
times, and circumstances
Specificity
A single exposure should cause a single disease
Temporality
, This one is the most important. The causal factor must precede
the disease in time. Exposure must come before the outcome.
This is the only one that is always required.
Biological gradient
A dose-response relationship, as the exposure increases, so does
the risk of the outcome
Plausibility/coherence
A biological or social model exists to explain the association.
Example: Cigarettes contain carcinogenic substances
Experiment
Investigator-initiated intervention that modifies the exposure
through prevention, treatment, or removal should result in less
disease
Analogy
Has a similar relationship been observed with another exposure
and/or disease
Interpreting relative measures of association
=1 --> no evidence or null
<1 --> negative or protective association
>1 --> positive or harmful association
This is the same for absolute measures of association, but the 1
turns to a 0
Example of interpreting a risk ratio
James Lind
One of the first clinical trials in humans , trial was focused on
preventing scurvy and discovered citrus fruit and vitamin c as
the solution
William Farr
Developed census data using marriages, deaths, and births. Used
a numerator and census data in the denominator
John Snow
The father of epidemiology because he created and rigorously
tested hypotheses. Discovered that cholera must be introduced to
the alimentary canal and accidentally swallowed. The increase
in morbid materials or cholera poison must take place in the
stomach and bowels
Strength of association
The larger the association, the more likely the exposure is to
cause the disease
Consistency
Association is observed repeatedly in different persons, places,
times, and circumstances
Specificity
A single exposure should cause a single disease
Temporality
, This one is the most important. The causal factor must precede
the disease in time. Exposure must come before the outcome.
This is the only one that is always required.
Biological gradient
A dose-response relationship, as the exposure increases, so does
the risk of the outcome
Plausibility/coherence
A biological or social model exists to explain the association.
Example: Cigarettes contain carcinogenic substances
Experiment
Investigator-initiated intervention that modifies the exposure
through prevention, treatment, or removal should result in less
disease
Analogy
Has a similar relationship been observed with another exposure
and/or disease
Interpreting relative measures of association
=1 --> no evidence or null
<1 --> negative or protective association
>1 --> positive or harmful association
This is the same for absolute measures of association, but the 1
turns to a 0
Example of interpreting a risk ratio
