Concept explainers
Exercises 37 through 40 refer to a clinical study conducted at the Houston Veterans Administration Medical Centre on the effectiveness of knee surgery to cure degenerative arthritis (osteoarthritis) of the knee. Of the 324 individuals who met the inclusion criteria for the study,
a. Was the sample chosen by random sampling? Explain.
b. Was this study a controlled placebo experiment? Explain.
c. Describe the treatment group(s) in this study.
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Excursions in Mathematics, Loose-Leaf Edition Plus MyLab Math with Pearson eText -- 18 Week Access Card Package
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