Answer:
Explanation:
There are so many factors to be considered in comparing two samples.
Here given that you want to test the effectiveness of a certain drug for treating a disease—that is, you want to see if using the drug is better the standard treatment.
To get accurate results, the following factors also should be considered
1) Age group of the two groups must be equal because sometimes age causes prone to diseases.
2) Food habits of the two groups -- certain food may enhance the chance of getting disease. So this should be taken into consideration
3) Family history about the parents already having that disease
4) Exercise and lifestyles of the groups
5) Environment, climate, etc of the two groups