This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
A cardiologist waewnts to study the effect of an atrovastatin drug. He notes down the initial cholesterol levels of 50 patients and then administers the drug on them. After a month’s treatment, he measures the cholesterol level again. Which of the following is the most appropriate to test the statistical significance of the change in blood cholesterol? 
Select and explain. 
A. Paired t-test, B. Unpaired or independent t-test, C. Analysis of variance, D. Chi-square test
A: Paired t-test
Answer: A: Paired t-test 
Explanation: In the given question, a cardiologist wants to study the effect of an atrovastatin drug; he notes down the initial cholesterol levels of 50 patients and then administers the drug on them and after a month’s treatment, he measures the cholesterol level again
Since mean cholesterol levels are being measured in the same group of individuals before and after an intervention, this is PAIRED DATA
Thus, the most appropriate to test the statistical significance of the change in blood cholesterol will be Students (paire(d) t-test.