In a recent communication, Goodin [1] analyzes several clinical trials to point out serious flaws in both design and interpretation that may invalidate the conclusions that are drawn. We agree with Goodin [1] that the design of clinical studies, particularly of a disease as complex as multiple sclerosis, is extremely difficult. Indeed, a perfectly designed and executed clinical study is a goal that is never achieved because of the problems inherent in providing care to patients while attempting to evaluate a therapeutic modality. Specifically, in the study of multiple sclerosis, none of the clinical trials of the use of interferons could be considered fully satisfactory: blinding is actually impossible because of the symptoms that are experienced by patients when they receive active drug but not when they receive placebo. It is quite fashionable and not at all difficult to find problems in the conduct of clinical studies; indeed, if all clinical studies with flaws were discarded, there would be no acceptable clinical studies.