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Explanatory Versus Pragmatic Approach in Controlled Clinical Trials, with Special References to Clinical Trials of Platelet-Active Drugs

  • E. Eschwege
  • D. Schwartz
Part of the Medizinische Informatik und Statistik book series (MEDINFO, volume 33)

Summary

A comparative trial may be undertaken with more than one aim in view. One type of objective is to ascertain whether a new treatment actually possesses the favourable activity in man which laboratory studies have led to expect. This is typical of the situation with a new drug or a new use for an old drug. In this case, the clinical trial, motivated by the same research-orientated attitude that the laboratory experimentation, requires the “top” conditions. Another type of objective is to assess the practical value of a new treatment in relation to other treatments: in this case, the advantages and drawbacks of the various possible treatments have to be taken into account with a view to making a recommendation for clinical practice. The trial is aimed at providing practising clinicians with a basis for decisions concerning the choice of therapy, and its motivation is strictly practical in nature. Finally, the explanatory or pragmatic problem formulation is determining for the choice of treatment, of patients, of criteria and of methods of comparison. The clinical trials of platelet-active drugs in coronary and cerebro-vascular diseases, started and completed in the last ten years, are discussed on basis of these two different approaches. Their aim was to demonstrate the efficacy of these drugs and all had an explanatory design. However, for most of them, the choice of purely pragmatic criteria for assessing outcome could explain the questionable and unsatisfying conclusions to which they ended. These examples show the necessity of an unambiguous formulation and a corresponding design of the tria.They underline the importance of strategy in the choice and the priorities of different trials.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1981

Authors and Affiliations

  • E. Eschwege
    • 1
  • D. Schwartz
    • 1
  1. 1.Institut National de la Santé et de la Recherche MédicaleUnité de Recherches StatistiquesVillejuifFrance

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