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What is In a study in UK, an association was found between sale of antiarrythmic drug and an increase in deaths due to asthma. This is an example of and explain in detail?
Ecological study [Ref: Park, 21/e p59 (19/e, p58) www.ucel.ac.uk.rlos/specs/rlo_observational_study.doc; Repeat Nov 10 & Nov 06 This is an example of ecological study. An ecological study is a type of Observational study where information is collected on a group (or population) rather than on individual members and then analyzed. Here the association between a summary measure of sale of antiarrythmic drugs (risk factor) and summary measure of deaths due to asthma (outcome) is studied. For detailed explanation see Nov10