Chapter 8, Problem 84P

Tennis elbow is a painful condition that afflicts many tennis players at some time. A number of different treatments are used for this condition, including rest, heat, and anti-inflammatory medications. A clinical trial was conducted among 87 participants, comparing the effectiveness of Motrin (generic name, ibuprofen), a widely used anti-inflammatory agent, vs. placebo. Participants received both drug and placebo, but the order of administration of the two was determined by randomization. Specifically, approximately half the participants (group A) received an initial 3-week course of Motrin, while the other participants (group B) received an initial 3-week course of placebo. After the 3-week period, participants were given a 2-week washout period during which they received no study Data set available medication. The purpose of the washout period was to eliminate any residual biological effect of the first-course medication. After the washout period, a second period of active drug administration began, with group A participants receiving 3 weeks of placebo, and group B participants receiving 3 weeks of Motrin. At the end of each active drug period as well as at the end of the washout period, participants were asked to rate their degree of pain compared with baseline (before the beginning of the first active drug period). The goal of the study was to compare the degree of pain while on Motrin vs. the degree of pain while on a placebo. This type of study is called a cross-over design, which we discuss in more detail in Chapter 13.

Degree of pain vs. baseline was measured on a 1−6 scale, with 1 being “worse than baseline” and 6 being “completely improved.” The comparison was made in four different ways: (1) during maximum activity, (2) 12 hours following maximum activity, (3) during the average day, and (4) by overall impression of drug efficacy. The data are given in Data Set TENNIS2.DAT with documentation in TENNIS2.

DOC, both at www.cengagebrain.com.

Answer Problem 8.81 for the overall impression of drug efficacy.

8.81 Compare degree of pain while on Motrin with degree of pain on placebo during maximal activity.