. 10.20 Biofeedback is a treatment technique in which people are trained to improve their health by using signals from their own bodies. Specialists in many different fields use biofeedback to help their patients cope with pain. A study was conducted to compare a biofeedback treatment for chronic pain with an NSAID medical treatment. A group of 2,000 newly diagnosed chronic pain patients were randomly assigned to receive to one of the two treatments. After 6 weeks of treatments, the pain levels of the patients were assessed with the following results: Significant Reduction in Pain Treatment Yes No Total Biofeedback 560 440 1,000 NSAID 680 320 1,000 Total 1,240 760 2,000 10.11 Exercises 537 a. For both treatments, place 95% confidence intervals on the proportions of patients who experienced a significant reduction in pain. b. Is there significant evidence (a = .05) of a difference in the two treatments relative to the proportions of patients who experienced a significant reduction in pain? c. Place a 95% confidence interval on the difference in the two proportions.