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Concept explainers
Type of Study. Determine whether the following studies are observational studies or experiments. If the study is an experiment, identify the control and treatment groups, and discuss whether single-or double-blinding is necessary. If the study is observational, state whether it is a case-control study, and if so, identify the cases and controls.
39. A double-blind drug versus placebo study of 103 patients suffering from tinnitus (the perception of ringing in the ears) demonstrated the effectiveness of ginkgo biloba extract. The ginkgo treatment improved the condition of all the tinnitus patients (Annals of Otology, Rhinolog,. and Laryngology).
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Chapter 5 Solutions
Using and Understanding Mathematics: A Quantitative Reasoning Approach plus NEW MyMathLab with Pearson eText -- Access Card Package (6th Edition) (Bennett Science & Math Titles)
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin HarcourtCollege Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
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