Concept explainers
Osteoporosis is an important cause of morbidity in middle- aged and elderly women. Several drugs are currently used to prevent fractures in postmenopausal women.
Suppose the incidence rate of fractures over a 4-year period is known to be 5% among untreated postmenopausal women with no previous fractures.
A pilot study conducted among 100 women without previous fractures aims to determine whether a new drug can prevent fractures. It is found that two of the women have developed fractures over a 4-vear period.
Is there a significant difference between the fracture rate in individual treated women and the fracture rate in the untreated women? (Report a two-tailed p-value.)
Suppose that 8 of the previous 100 women have developed abdominal pain during the trial, while only 1.5% would be expected to develop abdominal pain based on previous natural history studies.
Provide a 95% Cl for the rate of abdominal pain among the active treated women. Interpret the results compared with previous natural history studies.
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Fundamentals of Biostatistics
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- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL