Effects of risk perception of marijuana use on marijuana use and intentions to use among adolescents in Bogota, Colombia

Background: Perceived risk is a key concept of behavioral theories used to predict substance use among youth and a core component of drug use prevention interventions. The present study aimed to (1) assess degrees of risk perception of regular marijuana use, (2) identify factors associated with risk perception, and (3) explore the associations between perceived risk and marijuana use and intentions to use marijuana among school-attending adolescents in Bogota, Colombia. Methods: Data from 2079 standardized questionnaires administered in 23 schools were analyzed in this study. Schools were selected in a multi-stage probability cluster sample to reflect the socio-economic characteristics of Bogota's student population. Results: Just over 11% of participants perceived regular marijuana use to be a low risk behavior. Older age (>16 years) (adjusted odds ratio = 2.9; 95% confidence interval = 1.4-6.0) and low level of knowledge regarding the physical and psychological harms of illegal drugs (AOR = 2.9; 95%CI = 2.0-4.3) were the strongest predictors of low risk perception, Low perceived risk was also significantly associated with ever having used marijuana (AOR = 2.5; 95%CI = 1.7-3.7), monthly marijuana use among ever marijuana users (AOR = 2.7; 95%CI = 1.4-5.0), and a positive intention to use marijuana within the next 12 months among non-users (AOR = 2.1; 95%CI = 1.4-3.5). Conclusions: Consistent with previous findings, perceiving regular marijuana use as a risky behavior functions as a protective factor against the intention to use, use and occasional use of marijuana. Incorporation of this message into drug use prevention activities for non-users and early-stage users may enhance their effectiveness. (C) 2009 Elsevier Ireland Ltd. All rights reserved.