control group

1. A
2. B
3. C
4. D
5. E
6. F
7. G
8. H
9. I
10. J
11. K
12. L
13. M
14. N
15. O
16. P
17. Q
18. R
19. S
20. T
21. U
22. V
23. W
24. X
25. Y
26. Z
27. #

In a clinical trial, the group that does not receive the new treatment being studied. This group is compared to the group that receives the new treatment, to see if the new treatment in fact works. Whether a person receives the new treatment, or is part of the control, is determined by chance — random — not by choice.

Read more about clinical trials.

Audio contributed by: Marisa Weiss, M.D.