Statistical Approaches to the Use of Magnetic Resonance Imaging Data for Clinical Trials

  • P. Bruzzi
  • M. P. Sormani
Conference paper
Part of the Topics in Neuroscience book series (TOPNEURO)


The clinical endpoints that are conventionally used in clinical trials in multiple sclerosis (MS) are: (a) occurrence of exacerbations often expressed as a rate, and (b) disability, usually evaluated by means of the Expanded Disability Status Scale (EDSS) [1]. These two endpoints represent the two fundamental dimensions affecting the evolution of the disease and the quality of life of MS patients. However, from a statistical viewpoint, they have several drawbacks. First of all, they cannot be assessed objectively, and their reproducibility is low [2]. As a consequence, in treatment trials both the patient and the physician in charge of assessing the clinical endpoint should be blinded to the assigned treatment. This is not always possible, depending on the study design or the toxicity of the experimental treatment. Second, their correlation with the pathological changes associated with the activity of the disease is poor [3, 4]. Finally, the sensitivity of EDSS to change is moderate [5], and often trials lasting much longer than 2–4 years would be needed to establish the effect of a new treatment on EDSS. All these limitations decrease the statistical power and the reliability of clinical trials based on these two clinical endpoints, with implications on the size and duration of MS trials, as well as on their design.


Multiple Sclerosis Expand Disability Status Scale Clinical Endpoint Magnetic Resonance Imaging Data Negative Binomial Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Italia 1999

Authors and Affiliations

  • P. Bruzzi
    • 1
  • M. P. Sormani
    • 1
    • 2
  1. 1.Biomedical Technology Assessment, Advanced Biotechnology CenterUnit of Clinical Epidemiology and Trials, National Institute for Cancer Research, and BETAGenoaItaly
  2. 2.Neuroimaging Research Unit, Department of Neuroscience, Scientific Institute Ospedale San RaffaeleUniversity of MilanItaly

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