[Clinical trial of drugs: a study of the influence of information on adverse reactions on obtaining of informed consent]

Abstract

Background: One of the factors that might influence a subject when making his decision on his possible participation in a clinical trial (CT), is the amount of information supplied to him concerning the adverse reactions of the drug being investigated.

Methods: In order to assess this aspect, we performed a mock trial, designed as a phase 1 CT, among university students. We drew up two documents (A and B) containing the minimum information concerning the "CT" and the "drug under investigation". Both documents were exactly the same except that document A indicated the reduced information about the adverse reactions of isoniazide as per the Spanish Vademecum, whereas document B contained the much more extensive and detailed data indicated in the US PDR. These documents (A and B) were read and handed over to the students, divided in two groups A and B, respectively. The students who ignored at every moment that it was a mock "CT", had to decide, in writing and anonymously, whether they were ready or not to participate in the CT.

Results: 306 university students, 148 of the School of Medicine and 158 of Telecommunications participated. In groups A (n = 160) and B (n = 146), 49% and 47% belonged to the School of Medicine, respectively. 10.6% of the subjects of group A accepted to participate in the "CT", against 4.1% of those of group B, which shows a statistically significant difference (p less than 0.05).

Conclusions: It is concluded that the amount of information about adverse reactions supplied to the possible participants in a CT, is a factor that influences the recruitment rate.