c. (6 points) The study investigator is interested in whether the treatment is associated with relapse rates, so a Chi-Square test is conductal ... 23. (22 points) Cocaine addiction is hard to break. Addicts need cocaine to feel any pleasure, so perhaps giving them an antidepressant drug will help. A 3-year study with 48 chronic cocaine users compared an antidepressant drug called Desipramine with Lithium, which is a standard drug to treat cocaine addition, to examine. Half of the subjects, chosen at random, received each treatment. Here are the results: Relapse No Yes Total Treatment Dosipramine 14 10 18 Total 20 28 a. (2 points) What is the overall relapse rate from this study? (i.e., the proportion of all individuals that have a relapse, converted to a percentage). The overall relapse rate = ( 28 / 4 8 ) * 100 = 58: 33%% b. (4 points) Calculate the relapse rates for each of the two drugs in this study? Desipramine = ( 24 /48 ) # 100 = 50%% Lithium = ( 2 4 1 4 8 ) *10 0 = 50%