[Theater in the education of children and teenagers participating in a clinical trial].

OBJECTIVE To analyze the effects of a pedagogical intervention on the learning of children and teenagers participating in a clinical research. METHODS Quantitative, quasi-experimental and longitudinal study, part of a group of studies conducted to test a vaccine against ancylostomiasis. Convenience sample with 133 students aged 10-17 years, of both sexes, from the school Escola Municipal de Maranhão (Southeastern Brazil), 2009. A structured questionnaire was used, which was administered before and after the intervention. The pedagogical device was the "Theater of the Oppressed". The dependent variables were specific and global knowledge about clinical research and about parasitic worms; the independent variable was participation in the educational intervention. RESULTS There was an increase in knowledge about signals and symptoms, susceptibility to reinfection and way of contagion after the educational intervention. We observed an increase in the number of right answers concerning duration of clinical research, procedures, the possibility of quitting participation, and occurrence of adverse events. The notion that the research's primary purpose is therapeutic remained, but the percentage of participants who associated the research with medical treatment decreased. The "Theater of the Oppressed" enabled that the discussions about helminthiasis and clinical research were contextualized and materialized. The subjects could dispose of or reduce their previous representations. CONCLUSIONS Participation of children and adolescents in clinical trials must be preceded by an educational intervention, since individuals of that age group do not even recognize they have the right to decide for themselves.