Suspected cause preceding the observed effect is an example for-
Ans. is 'a' i.e., Temporal association Temporal associationo It implies cause preceds effect or effect follows cause, i.e., suspected cause preceding the observed effect,o It is the most important criteria for causal associationo It is best established by concurrent cohort study.Strength of associationo It implies how strongly exposure is associated with disease,o It is determined byiii) Dose-response relationship -With increasing level of exposure to the risk factor, on increasing ris in incidence is found.iv) Cessation of exposure (Reversibility) - Removal of possible cause reduces risk of disease.Consistency of associationo The association is consistent if the results are replicated when studies in different settings and by different methods.o For example, different studies in different settings have proved smoking as one of the cause for lung cancer - Smoking has consistent association with lung cancer.Coherence of associationo The causal association must be coherent (supported by) with relevant facts,o For exampleThe death rates due to lung cancer increasing more rapidly in females comparison to males.The relevant fact -This increasing rate is due to more recent adoption of cigarrete smoking by women.
Temporal association
Consistency of association
Strength of association
Coherence of association
Principles of Epidemiology