Drug use motives are relevant to understand substance use amongst students. Data mining techniques present some advantages that can help to improve our understanding of drug use issue. The aim of this paper is to explore, through data mining techniques, the reasons why students use drugs.A random cluster sampling of schools was conducted in the island of Mallorca. Participants were 9300 students (52.9% girls) aged between 14 and 18 years old (M = 15.59, SD = 1.17). They answered an anonymous questionnaire about the frequency and type of drug used, as well as the motives.Five classifiers techniques are compared; all of them have much better performance (% of correct classifications) than the simplest classifier (more repeated category: drug use/never drug use) in all the compared drugs (alcohol, tobacco, cannabis, cocaine). Nevertheless, alcohol and tobacco have the lower percentage of correct classifications concerning the drug use motives, whereas these use motives have better classification performance when predicts cannabis and cocaine use. When we analyse the specific motives that better predicts the category classification (drug use/never drug use), the following reasons are highlighted in all of them: “pleasant activity” (most frequent among drug users), and “friends consume” and “addiction” (both of them most frequent among never drug users). These results relate to the social dimension of drug use and agree with the statement that environmental context influences adolescent's involvement in risk behaviours. Implications of these results are discussed.

Alcohol use is a persisting social and health problem in Spain that often takes place within the recreational context. This study aims to analyze objective and self-reported measures of alcohol use and to assess the potential role of social factors on alcohol intake in open-air public settings. A total of 1475 participants (47.4% women), including 27.8% adolescents organized into 355 natural groups of friends, were interviewed while they were socializing at night in the streets of Palma (Spain). Breath alcohol concentration (BrAC), self-reported measures of alcohol use, and social variables were assessed. Men showed statistically higher scores in BrAC than women. However, adolescents’ Alcohol Use Disorders Identification Test (AUDIT) scores were not statistically different by gender. Correlation between objective and self-reported measures was low. Interestingly, BrAC of drinkers was lower when some friends in the group were sober. Moreover, especially in young adults, variables related to the social environment were statistically significant factors to predict BrAC. In conclusion, we found a high prevalence of alcohol intake in young people in open-air public settings, low relationship of objective and self-reported measures, and social factors linked to alcohol use, although differences by age and gender must be considered.

Parental mediation in the use of Information and Communication Technologies (ICTs) is a protective factor against adolescents' online risk behaviours. This study aimed to design an assessment scale of parental mediation referred by minors and to explore its structure and psychometric properties. A total of 560 secondary education students (47.5% girls) informed, in addition to parental mediation, about their habits of connection and online communication, privacy and risky online behaviour, and cyber-victimization. Data revealed a Parental Mediation Scale for ICTs (EMP-TIC) composed of 28 items distributed in five dimensions: active regulation, restrictive regulation, co-use, software monitoring and personal monitoring, which explain 55.98% of the variance. The dimensions of monitoring and co-use showed significant positive correlations with cyber-victimization. Higher scores in parental mediation are associated with greater privacy. The Parental Mediation Scale (EMP-TIC) structure is coherent to previous theoretical proposals. EMP-TIC shows adequate psychometric properties and provides information about the parental patterns in the use of ICTs. The scale can be used as a total score of parental mediation or for each of the five included domains. RESUMENLa mediación parental en el uso de las tecnologías de la información y la comunicación (TIC) es un factor de protección frente a las conductas de riesgo de los adolescentes en los entornos en línea. El objetivo de este estudio es diseñar una escala de evaluación de la mediación parental desde la perspectiva adolescente y explorar su estructura y propiedades psicométricas. Una muestra de 560 estudiantes de Educación Secundaria (47.5% chicas) facilitó información relevante, además de la mediación ARTICLE HISTORY