[Methodological and ethical quality in phase III cancer trials: role of the cooperative group]

Phase III clinical trials (CT) are carried out more and more often in a multicentric way, under the aegis of one or more cooperative groups (CG). The goal of this study was to analyze the influence of the GC on ethical quality (EQ) and methodological quality (MQ) in phase III cancer CT. EQ (Berdeu-score) and MQ (Jadad scale) were assessed for all CTs (n=231) published between 1999 and 2001 in 10 international journals. The impact of CG on EQ and MQ was evaluated with an univariate analysis. 140 ECR (60.6%) were carried out under the aegis of a CG. There was no improvement of the MQ and EQ for the trials carried out under the aegis of a CG. The methodological score (Jadad) was of 9.9 +/- 1.15 for the CT-CG (+) and of 9.8 +/- 1.28 for the CT-GC (-) (p=0.7). The ethical score (Berdeu) was of 0.43 +/- 0.14 for the CT-CG (+) and of 0.40 +/- 0.11 for the CT-CG (-) (p=0.08). Interim analysis, defined stopping rules and independent monitoring were more frequent for the CT-CG (+) and were respectively 37.8% vs 15.4%, 20.7% vs 8.8%, 19.3 vs 6.6%. 31.9% of the CT-CG (-) and 19.3% of the CT-CG (+) were financed by industry (p=0.03). The CG have a major role to play in the protection of the patient in CT, because they monitored trials from the conception to the publication and communication of results.