Attitudes, knowledge and sexual behavior among Finnish adolescents before and after an intervention.

Adolescents are an important target group for sexual health promotion, and there are numerous programs and interventions carried out in this field. The aim of this study is to describe adolescents' attitudes, knowledge and sexual behavior before and after a sexual health promotion intervention. The intervention was developed in the study and consisted of three elements: (i) class-room session, (ii) information materials and (iii) free condom distribution. The study was carried out in eight randomly selected vocational schools in Finland. The participants were first year students aged 15-19 years. The data were collected using an electronic questionnaire before intervention (intervention baseline n = 500, control baseline n = 183) and two times after the intervention (intervention first follow-up n = 173/second follow-up n = 202, control first follow-up n = 115/second follow-up n = 46). There were significant differences before and after the intervention concerning better knowledge and more frequent testing for sexually transmitted infections (STIs). Schools are an important environment to reach adolescents during the phase where their sexual health is developing and there is an increased risk of STI transmission. More school-based interventions are therefore needed, and the results of this study can be utilized when developing sexual health promotion interventions among adolescents.