Simultaneity of risk behaviors for sexually transmitted infections in Brazilian adolescents, 2012

to analyze the simultaneity of two groups of risk behaviors for sexually transmitted infections in Brazilian adolescents. cross-sectional study with data from the National Adolescent School-based Health Survey 2012; the outcomes were (1) simultaneous consumption of alcohol, tobacco and drugs (at least two), and (2) no use of condom and having two or more sexual partners. simultaneity of consumption of alcohol, tobacco and drugs was present in 14.7% of the boys and 21.5% of the girls, and was more prevalent among white individuals, with more educated mothers, and who did not live with their parents; approximately 12.0% of the adolescents presented simultaneity of no use of condom and having two or more sexual partners; this was more common among younger boys, not white (PR=1.22; 95%CI 1.10;1.36), and who did not live with their parents (PR=1.78; 95%CI 1.48;2.16), whilst among girls, this outcome was associated with higher age. both outcomes were associated with different characteristics, depending on the sex of the adolescent.