A patient with a COPD exacerbation is treated with prednisone 40 mg daily for one week with improvement. To discontinue the prednisone, the most appropriate procedure would be which of the following?

Which of the following is an advantage of a crossover-design clinical trial?

A 55 year old woman being treated for hypothyroidism with levothyroxine 125 mcg daily is currently euthyroid. She now has menopausal symptoms and is receiving conjugated estrogens.
What effect is this most likely to have on her thyroid function tests?

In designing a clinical trial, the method utilized to deal with inherent differences between groups is to:

A MEDLINE search fails to retrieve a clinical trial known by the searcher to have been published in a recently established open-access medical journal. This failure has most likely occurred because of which of the following?