Problems in Clinical Trial Design in Multiple Sclerosis

Historically, it has been difficult to demonstrate the effectiveness of treatments for multiple sclerosis (MS) because of the variability in the course of the disease, the lack of well-defined, reliable clinical measures, and the pervasiveness of poorly controlled clinical trials. Hence, to interpret the results of clinical trials in MS and make evidence-based decisions regarding treatment for their patients, neurologists should have a basic understanding of appropriate outcome measures and the necessary controls of a well-designed study. This paper reviews the controls required to test the efficacy of agents for the treatment of MS and offers examples of poorly controlled clinical trials to illustrate the problems in interpreting data without such controls. In addition, the outcome measures that should be used to assess the efficacy of treatments on the physical, inflammatory, and cognitive components of the disease are discussed. (Int J MS Care. 2002; 4: 125–131, 136–137)