correlational studies for drug effects
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Correlational Studies for Drug Effects. Alec Walker October 2014. Correlational Studies. Population frequency Population exposure Inference on association The problem of common cause. How we evaluate causal connections. Theory. Prediction. Data. Experiment. - PowerPoint PPT PresentationTRANSCRIPT
Correlational Studies
Population frequency Population exposure Inference on association The problem of common cause
Rheumatic Heart Disease at the House of the Good Samaritan, Boston, 1921-1920
4
Massell BF et al. N Engl J Med. 1988;318(5):280-6
Case Fatality
Clinical Course of Rheumatic Carditis
Loss of Murmurs
in rheumatic carditis patients in Boston
Case Fatality
A General Theory
Loss of Murmurs
in rheumatic carditis patients in Boston
Penicillin availability
Case Fatality
A Broader Prediction
Loss of Murmurs
in rheumatic carditis patients in Boston
Penicillin availability
National declines in
mortality from scarlet fever
and its complications
Case Fatality
A Broader Prediction
Loss of Murmurs
in rheumatic carditis patients in Boston
Penicillin availability
National declines in
mortality from scarlet fever
and its complications
Examine rates
Correlational Studies
Pay attention to the unit of observation Risk or rate is typically the metric Does observation unit stand as a proxy for
exposure? Does observation unit stand as a proxy for other
variable characteristics that predict outcome? Yes Confounding (“ecological fallacy”) No Instrument