The conduct of clinical trials for medicinal products in europe in the light of the European clinical trials directive. Review of regulatory and practical aspects in the different countries.

The purpose of the clinical trial guidelines is to harmonise legislation in order to ensure consistency within Europe and thereby promote Europe's attractiveness for clinical research while maintaining or improving the protection of subjects who agree to participate. The French administrative system has hitherto been relatively favourable (with simple notification to a single Ethics Committee per study); it is thus important to maintain competitiveness in these respects, given that, in other areas (the time it takes to establish agreements, recruitment, etc.), other countries have the advantage.

Quantification methods were developed for selection bias by predictability of allocations with unequal block randomization.

Background And Objective: A selection of patients for a controlled clinical trial may be biased because of prior knowledge of the treatment. With randomized blocks of known or guessed lengths, some allocations can be predicted with certainty. Previously described methods determine the proportion of predictable cases for blocks of equal lengths.