A scientist is designing a clinical trial to test the effect of online chat counseling with migraine sufferers as a supplementary treatment in combating their migraines. Migraine sufferers will have access to counselors via online chat software; the scientist plans to see whether their migraine pain has been reduced after six weeks.
If the trial doesn't include a control group, the data will be invalid because of:
A) the placebo effect.
B) lack of confidentiality.
C) the double-blind effect.
D) voluntary response.

Question

Quizplus · Accepted Answer

Without a control group, it will be difficult to determine whether any observed improvement in migraine pain is due to the actual treatment or the placebo effect. A control group would receive a placebo treatment, such as access to a chat room not staffed by counselors, to compare the effects of the treatment group against the effects of a placebo.

A Scientist Is Designing a Clinical Trial to Test the Effect