Concept explainers
Early Tonsillectomy for Children (Example
We randomly assigned
There were significantly greater improvements in behavioral, quality-of-life , and polysomnographic [sleep study] findings and significantly greater reduction in symptoms in the early-adenotonsillectomy group than in the watchful-waiting group….
a. Was the study a controlled experiment or an observational study? Explain how you know.
b. Assuming that the study was properly conducted, can we conducted that the early surgery caused the improvement? Explain.
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Introductory Statistics (2nd Edition)
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