Longitudinal study of a school based HIV/AIDS early prevention program for Mexican adolescents.

A quasi-experimental study is reported with four measurement occasions to evaluate longer-term effects of a life-skills and HIV/AIDS school-based prevention program. Trained teachers administered the program promoting precursors of safer sex behavior to 2064 Mexican high-school students at an age before most were sexually active. The variables included in the study (knowledge about HIV/AIDS prevention, attitudes towards use of condoms, subjective norms, intentions to use condoms and life skills as decision-making skills, partner communication and individual responsibility) have been reported as precursors of protective sexual behavior. The results demonstrate the stability of training effects and a positive impact on these precursors over 1 year of follow-up.