This study analyses two models (maternal and paternal) in which parental care and sources of parental knowledge moderated the relationship between parents' knowledge about their adolescents' lives and adolescents' substance use and health-related quality of life. The sample was made up of 15942 Spanish adolescents who participated in the 2006 edition of Health Behavior in School-aged Children Study. Results showed that increased parents' knowledge about their adolescents' lives reduced adolescents' substance use and increased their quality of life. With respect to the moderation relationship, a limited effect was found. However, parental care and sources of parental knowledge used by both parents generally had main effects on adolescents' substance use and health-related quality of life, with care being the most relevant variable in the health-related quality of life, while knowledge was the most relevant one for substance use.

The aim of this study was to evaluate the differences between adolescents with a high or low risk of developing an eating disorder (ED) in different health behaviors (eating habits, physical activity and the consumption of substances) per gender. The EAT-40 and the Inventory of Behavioral Health in Scholars were applied to 2142 middle school students from Alicante (Spain), of whom 52.8% were girls and 47.2% were boys, with an average age of 13.92 years old (Sd = 1.34). Results indicated that girls with a high risk of developing an ED consumed fewer meals, ate fewer unhealthy foods, followed more diets and paid more attention to nutritional components. Furthermore, they also performed more physical activity with the objective of losing weight, and consumed more tobacco, alcohol and medicines. Boys at high risk of developing an ED followed more diets and paid more attention to nutritional components. For boys, no more differences were found. These results suggest that any program directed at the prevention of ED should not only include nutritional education, but should also seek to promote regular physical activity with objectives other than weight loss or the burning of calories.

This research is part of the 2006 edition of the Health Behavior in School-aged Children (HBSC) study. The data presented were composed of a sample of 15942 Spanish adolescents ranging from 13 to 18 years of age. The instruments used included a variety of questions related to substance consumption among adolescents, their bio-psycho-social adjustment and developmental contexts, all of which are part of the HBSC study instrument bank. Through classification analysis, as well as significance and effect size tests, we obtained relevant information about the current epidemiology of substance consumption among Spanish adolescents. These results are representative of the Spanish adolescent population which allows the typical risk profile attributed to young people to be clarified. A gradual adjustment can be seen in terms of substance consumption levels in youth and that same level in their friends. Likewise, the analysis of the developmental context (family, friends and school) provides important information when it comes to preventing substance consumption, thus showing the advantages that coherence and connection have between the different environments where youth live, grow up and develop.