Dr.Nan is studying the effects of Ginseng on recall.He has 2 groups of subjects, (20 subjects in each group).Subjects are given Ginseng or Placebo and then asked to recall a list of words they previously studied.However,to avoid confounds what should Dr.Nan do?
A)Counterbalance placebo & Ginseng
B)Match groups on an IQ test and assign to groups
C)Randomly assign subjects to groups
D)All of these
E)Both b & c

Question

Quizplus · Accepted Answer

Matching groups on an IQ test and randomly assigning subjects to groups helps control for confounding variables, ensuring that differences in recall are due to the treatment rather than pre-existing differences.

DrNan Is Studying the Effects of Ginseng on Recall