Causal and Association
Clinical observations
Available data
Case-control studies
Cohort studies
Randomized trials
How to Start
-Approach observation
-Is there access risk
-Prove it (type of association) confounding factor
-Draw conclusion
-search for data or explanation
Causal relationship
-Necessary and sufficient, (single factor ) inf
-Necessary but not sufficient ,(multiple factors) CA
-Sufficient but not necessary, CA
-Neither sufficient nor necessary ,chronic diseases
Example
-Coffee ==== pancreatic ca === smocking
-High cholesterol ===CHD====genetic
-Smocking female==low birth weight===age
E.x:2
1-Consistency
2-Specificity
3-Temporality(timing )
4-Biological gradient
5-Plausibility
6-Coherence
7-Experimentation
8-Analogy
By:Brwa