4. Sickle-cell disease is a painful disorder of the red blood cells that, in the United States, affects mostly African Americans. To investigate whether the drug hydroxyurea can reduce the pain associated with sickle-cell disease, a study by the National Institutes of Health gave the drug to 150 sickle-cell sufferers and a placebo to another 150. Neither doctors nor patients were told who received the drug. The number of episodes of pain reported by each subject was recorded. This is an example of: a. an observational study. b. an experiment, but not a double-blind experiment. c. a double-blind experiment. d. a matched pairs experiment.

4. Sickle-cell disease is a painful disorder of the red blood cells that, in the United States, affects mostly African Americans. To investigate whether the drug hydroxyurea can reduce the pain associated with sickle-cell disease, a study by the National Institutes of Health gave the drug to 150 sickle-cell sufferers and a placebo to another 150. Neither doctors nor patients were told who received the drug. The number of episodes of pain reported by each subject was recorded. This is an example of: a. an observational study. b. an experiment, but not a double-blind experiment. c. a double-blind experiment. d. a matched pairs experiment.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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