Social & Preventive Medicine In a study in UK, an association was found between sale of anti-arrhythmic drug and an increase in deaths due to asthma. This is an example of:- A Ecological study B Coho study C Case reference study D Experimental study 💡 Explanation In a study in UK, an association was found between sale of anti-arrhythmic drug and an increase in deaths due to asthma. This is an example of:- ✓ Correct Answer: A. Ecological study