Dr. Know developed a new type of therapy for treating individuals’ depression. He wanted to find out if the therapy technique he had developed was effective and resulted in an amelioration of...

Dr. Know developed a new type of therapy for treating individuals’ depression. He wanted to find out if the therapy technique he had developed was effective and resulted in an amelioration of depression. Assume that he enlisted your aid in setting up a study that would test the effectiveness of this therapy. Identify the extraneous variables that could confound the results of this experiment, explain how the confounding would take place, and identify how you would control for these extraneous variables.