Tests of Significance and Confidence Intervals for Means 10. Hypersexual behavior caused by traumatic brain injury (TBI) is often treated with the drug Depo-Provera. In one clinical study, eight young male TBI patients who exhibited hypersexual behavior were treated weekly with 400 milligrams of Depo-Provera for six months (Journal of Head Trauma Rehabilitation, June, 1995). The testosterone levels [in nanograms per deciliter (ng/dL0)] of the patients both prior to treatment and at the end of the 6-month treatment period are given in the table below. Construct a 99% confidence interval for the true mean difference between the pretreatment and after- treatment testosterone levels of young male TBI patients. Assume normal distributions. Patient 2 3 4 5 6 7 8 Pre drug 849 903 890 1092 362 900 1006 672 On drug 696 741 731 1024 246 853 1113 774