Question: 37 A treatment trial is proposed to test the efficacy of vitamin E as a preventative agent for cancer. One problem with such a study is how to assess compliance among participants. A small pilot study is undertaken to establish criteria for compliance with the proposed study agents. In this study, 10 patients are given 400 IU/day of vitamin E and 10 patients are given similar-sized tablets of placebo over a 3-month period. Their serum-vitamin E levels are measured before and after the 3-month period, and the change (3-month baseline) is shown in Table 5.2

Is the measure in Problem 5.36 a measure of sensitivity, specificity, or predictive value? Why?