The following paragraphs are taken from the article, "Antibiotics' Role in Heart Attacks to Be Focus of Study." (Source: The Morning Call, April 5, 1999.)
"Could taking an antibiotic spare heart patients future heart attacks, bypass surgery or death?
"Researchers hope to find out with a large, federally funded study based on growing evidence a common bacterial infection that can lie dormant for years might trigger heart attacks and worsen, perhaps even cause, atherosclerosis? narrowing of the arteries from plaque deposits.
"Half of the 4,000 heart disease patients to be studied will be given a weekly antibiotic pill, Zithromax, for one year, while the comparison group gets a dummy pill. Neither will know who is taking which pill."
Is this an observational study or an experiment?
Identify the population and the sample described in the study.
Identify the explanatory variable(s) and the response variable(s).
Identify the source of any potential bias.
The "dummy pill" referred to in the article is also called a placebo. Why might that be an important consideration in a study such as this one?
This is a observational study. The population are people with heart disease. The scientist will study four thousand of them. The response variable is the heart attacks, and atherosclerosis. The explanatory variable are ...
An antibiotics student is provided. The expert determines whether antibiotics could space heart patients future heart attacks.