As for the doses compared in the JAMA study:
We excluded patients whose initial daily dose of corticosteroids fell outside a conventional range of treatment. This included patients who received less than 20 mg or more than 80 mg of oral prednisone and those treated intravenously at doses lower than 120 mg or higher than 800 mg of prednisone equivalents each day.
I was a little bit surprised at the claim that the guidelines recommend lower dose oral therapy, so I checked the primary sources. Sure enough, ATS, Global Initiative and ICSI guidelines all recommend oral therapy for patients who can tolerate PO, in the range of 40 mg or so of prednisone per day.
This will probably change my practice but I'm not sure how, just yet. The fact that 22% of patients started on PO crossed over into the IV group bothers me a little bit.
Med Page Today's video interview with one of the authors is shown here.