Further investigation of psychological and environmental correlates of substance use in adolescence in six European countries.

Aim: To study the multifactorial correlates of adolescents' use of legal and illegal substances in six European countries and to assess whether a common pattern of factors exists irrespective of the countries' different sociocultural backgrounds.

Design: Cross-sectional European school population survey (ESPAD) following standardized methodology.

Participants: National probability samples of 16-year-old high school students from Bulgaria, Croatia, Greece, Romania, Slovenia and the UK.