Pitfalls in Clinical Research. The Case of the New Antineoplastic Agents

Pitfalls nella ricerca clinica. Il caso dei nuovi farmaci in Oncologia

Abstract

Pitfalls are often present in clinical research. In this paper, we highlight some shortcomings affecting the comparative studies on the efficacy of the new drugs in Oncology. More precisely, we will focus on the frequent choice of an intermediate endpoint - instead of the final endpoint of effectiveness - and the also frequent practice to allow the patient to crossover to the alternative treatment, when the proof of a greater effectiveness has not yet been reached. The effects of the Bonferroni's inequality on the results of a clinical study, and the choice of the comparator, as well as the use of the placebo, are also discussed. Finally, the importance of an appropriate procedure to determine the appropriate sample size is pointed out. An example from published studies is presented after the discussion of each issue.