

MCQOPTIONS
Saved Bookmarks
1. |
_Which of the following is not a problem associated with observational studies?$? |
A. | The main conclusion may be invalid because of the confounding effects of uncontrolled variables |
B. | Estimates may be biased because of non-random sampling |
C. | Observations have to be taken on groups of individuals rather than on individuals themselves |
D. | None of the above |
Answer» E. | |