Dr.Reside treated 20 children using a new therapeutic procedure.An outside observer rated the children's activity level on a laboratory task before and after the treatment; 80% of the children decreased their activity level following treatment,and Dr.Reside concluded that the procedure was highly effective.What is the major problem with Dr.Reside's experiment?
A)lack of control group
B)lack of a double-blind procedure
C)no baseline measure
D)the observer was biased

Question

Quizplus · Accepted Answer

The major problem with Dr. Reside's experiment is the lack of a control group. Without a control group, it is impossible to know if the observed changes in activity level were actually caused by the therapeutic procedure or by some other factor. A control group is necessary to rule out alternative explanations for the observed results.

DrReside Treated 20 Children Using a New Therapeutic Procedure