Pornography Use Profiles and the Emergence of Sexual Behaviors in Adolescence.

This research longitudinally explored adolescent pornography (porn) consumption and its association with sexual development in early and middle adolescence. A four-wave design with half-year intervals investigated pornography consumption and different (sexual) activities, such as masturbation, French kissing, petting, giving/receiving manual and oral sex, and intercourse, among 630 respondents (47.9% female, mean age 13.7 years; SD = 0.48) years at T1). A latent growth mixture analysis of pornography consumption revealed two groups with relatively low pornography (LP; 51.8% of the boys, 91.4% of the girls) versus high pornography (HP; 48.2% of the boys; 8.6% of the girls) consumption across time. At T1, HP boys on average watched pornography less than once a month, but more than once a year at T1. At T4, their average pornography use had increased to almost one to two times a week. LP boys never watched pornography at T1. At T4, their average pornography use was still less than once a year. At T1, HP girls never watched pornography, but consumption increased to almost one to three times a month at T4. Across waves of the study, LP girls (almost) never watched pornography. A discrete-time survival mixture analysis of sexual developmental patterning indicated that, compared to their LP peers, both girls and boys in the HP groups showed accelerated development of masturbation, petting, and receiving manual sex. Girls in the HP group were also more inclined to receive oral sex, whereas boys in the HP group also showed earlier and more frequent manual sex and intercourse. Thus, whereas the HP group of boys was substantially larger compared to that of girls, pornography consumption was related to accelerated development of sexual activities for both genders across early and middle adolescence. The discussion deliberates on pornography as a driving force in adolescent sexual development versus pornography as a medium of choice for sexually advanced adolescents.

Social Media Use and Adolescents' Sleep: A Longitudinal Study on the Protective Role of Parental Rules Regarding Internet Use before Sleep.

The popularity of social media use among adolescents has raised concerns about the potentially harmful effects of social media use on adolescents' sleep. Since longitudinal research considering this relationship is scarce, the present two-wave longitudinal study of 2021 secondary school students (Mage = 13.86, SD = 1.25) examined whether frequency of social media use and problematic social media use predicted adolescents' bedtime and quality of sleep. Moreover, the protective role of parental rules regarding Internet and smartphone use one hour before sleep was examined. The findings indicated that strict parental rules about Internet and smartphone use before sleep might prevent negative consequences of social media use on bedtime and sleep quality, but only among less engaged social media users. Once adolescents are highly engaged social media users, strict parental rules do not seem to prevent negative media influences on sleep. This implies that limiting Internet accessibility before bedtime can help prevent adolescents' sleep problems, but that regulation is less effective for adolescents who are already highly involved in social media use.

A Scale for the Assessment of Sexual Standards Among Youth: Psychometric Properties.

The (hetero)sexual double standard (SDS), prescribing sexual modesty for girls and sexual prowess for boys, negatively affects sexual and mental health. Nevertheless, endorsement and enactment of the SDS is still common. In this study, we respond to recent calls for modernization in the field of sexual double standard research. We describe the development of the "Scale for the Assessment of Sexual Standards among Youth" (SASSY), as well as its psychometric properties. This instrument was designed to measure contemporary sexual double standard endorsement, defined as "the degree to which an individual's attitude reflects a divergent set of expectations for boys and girls, in that boys are expected to be relatively more sexually active, assertive, and knowledgeable and girls are expected to be relatively more sexually reserved, passive, and inexperienced" among adolescents and emerging adults. In Study 1, a pool of 35 items was administered in a Dutch sample (N = 465, 54.8% female, age 16-20). A 20-item set formed a one-dimensional and internally consistent scale and was subsequently administered in a second Dutch sample. Study 2 (N = 818, 58.4% female, age 16-25) again assessed the 20-item set. After dropping one item, the 19-item SASSY proved to be one-dimensional and internally consistent, exhibiting good test-retest reliability, construct validity, and convergent validity. Finally, the instrument showed configural and metric measurement invariance across gender, age, education level, and sexual experience level, and configural, metric, and scalar measurement invariance across time. These studies confirmed the 19-item SASSY to be a reliable and valid new tool for the assessment of contemporary sexual double standard endorsement among adolescents and emerging adults.

The Impact of Personal Gender-Typicality and Partner Gender-Traditionality on Taking Sexual Initiative: Investigating a Social Tuning Hypothesis.

Sexual assertiveness is an issue of interest in the context of gender equality and sexual health. This study investigated the social tuning hypothesis that encountering a gender-traditional partner would lead to stronger gender-typical behavior, i.e., respectively, higher and lower levels of taking sexual initiative among men and women. Participants (N = 271) read a vignette describing a romantic partner, who was either presented as gender-traditional or not, followed by a sexual scenario. Subsequently, participants were asked about their expectations toward their own sexual initiative taking. Results showed a significant 'target gender-traditionality × participant gender × participant gender-typicality (masculinity/femininity)' interaction meaning that less gender-typical men were more likely to initiate sexual contact in the experimental, compared to the control condition. Men low in masculine characteristics showed higher initiative taking in response to a gender-traditional target female. We conclude that less gender-typical men seem to employ more social tuning toward their sexual partner, whereas more gender-typical men seem to adhere to their gender-typical behavior regardless of perceived partner characteristics. These results were not seen among the women in the sample. These findings are a starting point for the further development of experimental investigations regarding the gendered nature of both sexual initiative taking and sexual assertiveness in general.

Dutch Adolescents' Motives, Perceptions, and Reflections Toward Sex-Related Internet Use: Results of a Web-Based Focus-Group Study.

The Internet offers adolescents unique opportunities to actively shape their own sexual media environment. The aim of this study was to gain in-depth insight into Dutch adolescents' motives, perceptions, and reflections toward Internet use for (a) finding information or advice related to romance and sexuality; (b) searching for and viewing pornographic or erotic material; and (c) romantic and sexual communication (i.e., cybersex/sexting). Data were collected through 12 Web-based focus groups (36 adolescents aged 16 to 19 years, 72.2% girls) and analyzed through three stages of open, axial, and selective coding. The themes that emerged from the focus-group discussions suggest that sex-related Internet use is a complex and ambivalent experience for adolescents. Sex-related Internet use seems an increasingly normalized and common phenomenon. Participants perceived the Internet as a useful source of sexual information, stimulation, inspiration, and communication. Yet they discussed a range of negative consequences and risks related to sex-related online behaviors, particularly concerning pornography's potential to create unrealistic expectations about sex and sexual attractiveness. Participants generally believed they had the necessary skills to navigate through the online sexual landscape in a responsible way, although they believed other young people could be influenced inadvertently and adversely by sex-related online content.

Individual Popularity, Peer Group Popularity Composition and Adolescents' Alcohol Consumption.

Previous studies have convincingly shown associations between popularity and adolescent drinking. This study examined whether the popularity composition of the peer group and the relative difference in popularity between adolescents and their peers are also associated with adolescent drinking. Participants were 800 adolescents (M age = 14.73; SDage = 1.00; 51.6 % girls) from 31 classrooms who completed peer ratings of popularity and self-reports of alcohol consumption. Results showed that drinking was higher among popular than unpopular adolescents, higher among popular adolescents surrounded by less popular classmates, and lower in classrooms with more variability in popularity. Thus, beyond individual popularity, peer group popularity composition also should be taken into account when investigating antisocial and health risk behaviors in adolescence such as drinking.

The Relationship Between Endorsement of the Sexual Double Standard and Sexual Cognitions and Emotions.

Sexual gender norms promoting sexual prowess for men, but sexual modesty for women have been shown to negatively affect sexual and mental health in both men and women. Knowledge about the relationship between gender norms and sexual cognitions and emotions might further the understanding of continued gender-norm conformity. In the present study, we investigated whether and how gendered sexual attitudes are related to (positive and negative) sex-related emotions, via sexual cognitions (autonomy, body esteem, and approach/avoidance motives for sex). A survey was submitted to 293 heterosexually identified, sexually active, Dutch (central and southern regions) 18-25 year-olds. Results from a moderated mediation model (using structural equation modeling) revealed that women, but not men, who more strongly endorsed traditional gender-related sexual attitudes experienced significantly less positive and more negative emotions, as a result of decreased sexual autonomy and sexual body esteem as well as increased avoidance motives for sex. We conclude that, as a result of negative cognitions associated with the endorsement of traditional gender norms, women in particular are at risk of experiencing negative emotional outcomes in the sexual context. We argue that sexual cognitions and emotions deserve explicit attention in sex-positive and gender-transformative sexuality education, which has been proven to be a vital resource for achieving increased gender-equity in sexual and romantic relationships.

Psychosexual Correlates of Sexual Double Standard Endorsement in Adolescent Sexuality.

Endorsement and enactment of the (hetero)sexual double standard (SDS), prescribing sexual modesty for girls and sexual prowess for boys, has been shown to be negatively related to sexual and mental health. To be able to challenge the SDS, more insight is needed into the conditions that shape gendered sexual attitudes. A survey was conducted among 465 heterosexual adolescents (aged 16-20 years), examining the relationship between a number of relevant demographic and psychosexual variables and SDS endorsement. SDS endorsement was assessed using a newly developed instrument, the Scale for the Assessment of Sexual Standards Among Youth (SASSY). Gender (being male) and religiousness were significantly associated with increased SDS endorsement. For both boys and girls, increased feelings of entitlement to self-induced sexual pleasure (e.g., masturbation) were significantly associated with reduced SDS endorsement, whereas higher gender investment was significantly associated with increased SDS endorsement. Furthermore, increased feelings of entitlement to partner-induced sexual pleasure and more frequent talking about sexuality with peers were associated with increased SDS endorsement among boys but not among girls. We conclude that future research should explore peer influence processes through peer communication about sex, gender investment, and feelings of entitlement to both self and partner-induced sexual pleasure.

Lower Psychological Well-Being and Excessive Sexual Interest Predict Symptoms of Compulsive Use of Sexually Explicit Internet Material Among Adolescent Boys.

Although a growing body of literature addresses the effects of young people's use of sexually explicit Internet material, research on the compulsive use of this type of online content among adolescents and its associated factors is largely lacking. This study investigated whether factors from three distinct psychosocial domains (i.e., psychological well-being, sexual interests/behaviors, and impulsive-psychopathic personality) predicted symptoms of compulsive use of sexually explicit Internet material among adolescent boys. Links between psychosocial factors and boys' compulsive use symptoms were analyzed both cross-sectionally and longitudinally with compulsive use symptoms measured 6 months later (T2). Data were used from 331 Dutch boys (M age = 15.16 years, range 11-17) who indicated that they used sexually explicit Internet material. The results from negative binomial regression analyses indicated that lower levels of global self-esteem and higher levels of excessive sexual interest concurrently predicted boys' symptoms of compulsive use of sexually explicit Internet material. Longitudinally, higher levels of depressive feelings and, again, excessive sexual interest predicted relative increases in compulsive use symptoms 6 months later. Impulsive and psychopathic personality traits were not uniquely related to boys' symptoms of compulsive use of sexually explicit Internet material. Our findings, while preliminary, suggest that both psychological well-being factors and sexual interests/behaviors are involved in the development of compulsive use of sexually explicit Internet material among adolescent boys. Such knowledge is important for prevention and intervention efforts that target the needs of specific problematic users of sexually explicit Internet material.

Adolescents' use of sexually explicit Internet material and their sexual attitudes and behavior: Parallel development and directional effects.

Although research has repeatedly demonstrated that adolescents' use of sexually explicit Internet material (SEIM) is related to their endorsement of permissive sexual attitudes and their experience with sexual behavior, it is not clear how linkages between these constructs unfold over time. This study combined 2 types of longitudinal modeling, mean-level development and cross-lagged panel modeling, to examine (a) developmental patterns in adolescents' SEIM use, permissive sexual attitudes, and experience with sexual behavior, as well as whether these developments are related; and (b) longitudinal directionality of associations between SEIM use on the 1 hand and permissive sexual attitudes and sexual behavior on the other hand. We used 4-wave longitudinal data from 1,132 7th through 10th grade Dutch adolescents (M(age) T1 = 13.95; 52.7% boys) and estimated multigroup models to test for moderation by gender. Mean-level developmental trajectories showed that boys occasionally and increasingly used SEIM over the 18-month study period, which co-occurred with increases in their permissive attitudes and their experience with sexual behavior. Cross-lagged panel models revealed unidirectional effects from boys' SEIM use on their subsequent endorsement of permissive attitudes, but no consistent directional effects between their SEIM use and sexual behavior. Girls showed a similar pattern of increases in experience with sexual behavior, but their SEIM use was consistently low and their endorsement of permissive sexual attitudes decreased over the 18-month study period. In contrast to boys, girls' SEIM use was not longitudinally related to their sexual attitudes and behavior. Theoretical and practical implications of these gender-specific findings are discussed. (PsycINFO Database Record

Sex-Related Online Behaviors, Perceived Peer Norms and Adolescents' Experience with Sexual Behavior: Testing an Integrative Model.

Research on the role of sex-related Internet use in adolescents' sexual development has often isolated the Internet and online behaviors from other, offline influencing factors in adolescents' lives, such as processes in the peer domain. The aim of this study was to test an integrative model explaining how receptive (i.e., use of sexually explicit Internet material [SEIM]) and interactive (i.e., use of social networking sites [SNS]) sex-related online behaviors interrelate with perceived peer norms in predicting adolescents' experience with sexual behavior. Structural equation modeling on longitudinal data from 1,132 Dutch adolescents (M(age) T1 = 13.95; range 11-17; 52.7% boys) demonstrated concurrent, direct, and indirect effects between sex-related online behaviors, perceived peer norms, and experience with sexual behavior. SEIM use (among boys) and SNS use (among boys and girls) predicted increases in adolescents' perceptions of peer approval of sexual behavior and/or in their estimates of the numbers of sexually active peers. These perceptions, in turn, predicted increases in adolescents' level of experience with sexual behavior at the end of the study. Boys' SNS use also directly predicted increased levels of experience with sexual behavior. These findings highlight the need for multisystemic research and intervention development to promote adolescents' sexual health.

Trends in the co-occurrence of tobacco and cannabis use in 15-year-olds from 2002 to 2010 in 28 countries of Europe and North America.

BACKGROUND: Cannabis and tobacco use frequently co-occur. Adolescents who consume both substances experience more respiratory distress and psychosocial problems and are less likely to stop compared with those who use either tobacco or cannabis alone. This study examined time trends in tobacco and cannabis use among 15-year-olds in Europe and North America between 2002 and 2010. METHODS: Twenty-eight countries were included and merged into six regions based on their welfare systems. Adolescents (n = 142 796) were divided in four 'user groups': 'no-users', 'tobacco and cannabis users', 'tobacco-only users' and 'cannabis-only users'. Prevalence rates are reported by study-wave and region. Logistic regressions with study wave as independent variable were used to study trends in the user groups and regions. Interaction effects between time and gender were considered. RESULTS: Overall, tobacco use, and concurrent tobacco and cannabis use decreased by 3 and 3.7%, respectively, but prevalence rates varied by region. Only in North America, an interaction effect between time and gender was found in tobacco and cannabis users. CONCLUSIONS: Although this study demonstrates a decrease in tobacco and cannabis use in most regions, it also shows that the use of both substances is related. Therefore, studying the co-occurring use of tobacco and cannabis is necessary.

Frequent electronic media communication with friends is associated with higher adolescent substance use.

OBJECTIVES: This study investigated the unique associations between electronic media communication (EMC) with friends and adolescent substance use (tobacco, alcohol, and cannabis), over and beyond the associations of face-to-face (FTF) interactions with friends and the average level of classroom substance use. METHODS: Drawn from the cross-national 2009/2010 Health Behaviour in School-aged Children (HBSC) study in The Netherlands, 5,642 Dutch adolescents (Mage = 14.29) reported on their substance use, EMC, and FTF interactions. Two-level multilevel analyses (participants nested within classrooms) were run. RESULTS: Electronic media communication was positively associated with adolescent substance use, though significantly more strongly with alcohol (ß = 0.15, SEß = 0.02) than with tobacco (ß = 0.05, SEß = 0.02, t (5,180) = 3.33, p < 0.001) or cannabis use (ß = 0.06, SEß = 0.02, t (5,160) = 2.79, p < 0.01). Further, EMC strengthened several positive associations of FTF interactions and average classroom substance use with adolescent substance use. CONCLUSIONS: Electronic media communication was uniquely associated with substance use, predominantly with alcohol use. Thus, adolescents' EMC and other online behaviors should not be left unnoticed in substance use research and prevention programs.

Differential developmental profiles of adolescents using sexually explicit internet material.

This study used a person-centered approach to examine whether different developmental trajectories of boys' and girls' use of sexually explicit Internet material (SEIM) exist, which factors predict these trajectories, and whether sexual behavior develops differently for adolescents in these trajectories. A combination of latent class growth analysis on SEIM use and latent growth curve analysis on sexual behavior was used on four-wave longitudinal data of 787 eighth through tenth grade Dutch adolescents. Among boys, four SEIM use trajectories were identified, which were labeled Nonuse/Infrequent Use, Strongly Increasing Use, Occasional Use, and Decreasing Use. Among girls, a large Stable Nonuse/Infrequent Use and smaller Strongly Increasing Use and Stable Occasional Use trajectories were distinguished. Higher initial levels and/or stronger increases in SEIM use were predicted by demographic, social contextual, personal, and media use characteristics, including a stronger sexual interest, a higher degree of perceived realism regarding sexualized Internet content, and more permissive sexual attitudes. Moreover, initial levels of and, to some extent, developmental changes in sexual behavior varied for boys and girls in the different SEIM use trajectories. Whereas some adolescents showed concurrent low levels, or parallel strong increases in SEIM use and sexual behavior, a subgroup of boys decreased their SEIM use while increasing their sexual behavior.

Cross-national evidence for the clustering and psychosocial correlates of adolescent risk behaviours in 27 countries.

BACKGROUND: According to Jessor's Problem Behaviour Theory (PBT) and Moffitt's theory of adolescence-limited antisocial behaviour, adolescent risk behaviours cluster and can be predicted by various psychosocial factors including parent, peer and school attachment. This study tested the potential influence of the sociocultural, or macro-level, environment on the clustering and correlates of adolescent risk behaviour across 27 European and North American countries. METHODS: Analyses were based on data from the 2009-10 Health Behaviour in School-aged Children (HBSC) study. Participants compromised 56,090 adolescents (M(age) = 15.5 years) who self-reported on substance use (tobacco, alcohol, cannabis) and early sexual activity as well as on psychosocial factors (parent, peer and school attachment). RESULTS: Multiple group confirmatory factor analyses (with country as grouping variable) showed that substance use and early sexual activity loaded on a single underlying factor across countries. In addition, multiple group path analyses (with country as grouping variable) showed that associations between this factor and parent, peer and school attachment were identical across countries. CONCLUSION: Cross-national consistencies exist in the clustering and psychosocial correlates of substance use and early sexual activity across western countries. While Jessor's PBT stresses the problematic aspects of adolescent risk behaviours, Moffitt emphasizes their normative character. Although the problematic nature of risk behaviours overall receives more attention in the literature, it is important to consider both perspectives to fully understand why they cluster and correlate with psychosocial factors. This is essential for the development and implementation of prevention programmes aimed at reducing adolescent risk behaviours across Europe and North America.

Sex-related online behaviors and adolescents' body and sexual self-perceptions.

BACKGROUND AND OBJECTIVE: This study investigated: (1) the prevalence and development of 2 receptive (sexually explicit Internet material [SEIM] use and sexual information seeking) and 2 interactive (cybersex and general social networking site [SNS] use) online behaviors in adolescence; (2) whether development of these behaviors predict adolescents' body and sexual self-perceptions; and (3) whether parental strategies regarding adolescents' Internet use reduce engagement in sex-related online behaviors. METHODS: Four-wave longitudinal data among 1132 seventh- to 10th-grade Dutch adolescents (mean age at wave 1: 13.95 years; 52.7% boys) were collected. Developmental trajectories of sex-related online behaviors were estimated by using latent growth curve modeling. Self-perception outcomes at wave 4 and parental strategies predicting online behaviors were investigated by adding regression paths to growth models. RESULTS: Boys occasionally and increasingly used SEIM. Patterns for girls' SEIM use and boys' and girls' sexual information seeking and cybersex were consistently low. SNS use, however, was a common, daily activity for both. Higher initial levels and/or faster increases in sex-related online behaviors generally predicted less physical self-esteem (girls' SNS use only), more body surveillance, and less satisfaction with sexual experience. Private Internet access and less parental rule setting regarding Internet use predicted greater engagement in sex-related online behaviors. CONCLUSIONS: Although most sex-related online behaviors are not widespread among youth, adolescents who engage in such behaviors are at increased risk for developing negative body and sexual self-perceptions. Particular attention should be paid to adolescents' SNS use because this behavior is most popular and may, through its interactive characteristics, elicit more critical self-evaluations. Prevention efforts should focus on parents' role in reducing risky sex-related online behaviors.

Young adolescents' sexual and romantic reference displays on Facebook.

PURPOSE: Social networking sites (SNSs) form increasingly popular venues for adolescents to express their developing identity, including their sexual self. This study investigated how and to what extent early and middle adolescents display sexuality and romance on SNSs and the demographic and psychosexual factors associated with their displays. METHODS: Dutch adolescents aged 11-18 years were recruited and Facebook friended. Participants' Facebook profiles were evaluated for sexual and romantic references and Facebook engagement. Participants completed a digital questionnaire measuring constructs related to romantic and sexual development. Analyses included chi-square and Student's t-tests. RESULTS: A total of 104 adolescents (M(age) = 15.01, 68.3% female) were Facebook friended. Of 104 profiles, 25 (24.0%) contained 67 sexual references, and 27 (26.0%) contained 204 romantic references. Sexual references were mostly posted by others and referring to others or to no one in particular, whereas romantic references were predominantly posted by and referring to the profile owner. Displayers of sexual and romantic references were, compared with nondisplayers, older, more engaged in Facebook, more sexually experienced, and perceived more of their peers as approving of sex and as sexually active. In addition, sexual displayers were more likely boys and more sexually interested. There were no differences with respect to sexual intention and sexual attitudes. CONCLUSIONS: A minority of young adolescents display sexual and romantic references on SNSs. References may reflect adolescents' offline sexual and romantic experiences. Yet, they may be powerful in creating behavioral norms; therefore, guidance on interpreting and displaying such messages should be promoted.

Macro-level age norms for the timing of sexual initiation and adolescents' early sexual initiation in 17 European countries.

PURPOSE: To examine the relationship between country-level age norms for sexual initiation timing and early sexual initiation (ESI) among adolescent boys and girls. METHODS: Nationally representative data from 17 countries that participated in the 2006/2007 European Social Survey (ESS-3, n = 33,092) and the 2005/2006 Health Behaviour in School-Aged Children Study (HBSC, n = 27,702) were analyzed. Age norms were measured as the average country-level response to an item asking the age at which ESS respondents believed someone is too young to have sexual intercourse. HBSC respondents (aged 14-16 years) self-reported age at sexual initiation, which we defined as early (<15 years) or not early (≥15 years or no initiation). Control variables included age, family affluence, perceived socioeconomic status, family living arrangement, substance use, school attachment, and country-level legal age of consent. Multivariable three-level logistic models with random intercepts were run separately by sex. RESULTS: In multivariable analyses, higher overall age norms were associated with reduced likelihood of ESI among girls (AOR .60, 95% CI .45-.79); associations with ESI were stronger for parent cohort (ages 31-65 years) norms (AOR .37, 95% CI .23-.58) than for peer cohort (ages 15-20 years) norms (AOR .60, 95% CI .49-.74). For boys, overall norms were also significantly negatively associated with ESI (AOR .68, 95% CI .46-.99), as were parent cohort norms (AOR .66, 95% CI .45-.96). Peer cohort norms were not significantly related to boys' ESI. CONCLUSION: Macrolevel cultural norms may impact adolescents' sexual initiation timing. Research exploring the sexual health outcomes of early initiators in countries with contrasting age norms is warranted.

Trends in alcohol-specific parenting practices and adolescent alcohol use between 2007 and 2011 in the Netherlands.

BACKGROUND: Following increased research and policy attention on the harmful effects of alcohol use among adolescents and the implementation of prevention programs aimed at reducing adolescent alcohol use, this study examined whether alcohol-specific parenting practices have become stricter and whether adolescent alcohol use has declined between 2007 and 2011 in the Netherlands. METHODS: Data were derived from three nationally representative cross-sectional studies of 12 to 16-year old adolescents - the Dutch National School Survey on Substance Use (2007 and 2011) and the Health Behaviour in School-aged Children (2009). These data were obtained using self-report questionnaires in the classroom (adolescents, Mage=13.8 years, SD=.04) and at home (parents). RESULTS: Between 2007 and 2011, Dutch parents increasingly adopted strict alcohol-specific practices, except for parents of 16-year old adolescents. Furthermore, adolescent reports of lifetime and last month alcohol use decreased, except for 16-year olds. The quantity of alcohol consumed by adolescents did not change between 2007 and 2011. Alcohol-specific parenting practices were associated with lower adolescent alcohol use. These associations were generally stable over time. CONCLUSION: Our findings are consistent with the recent increased awareness in research, policy and the media about the harmful effects of alcohol on young people. Specifically, they are consistent with the focus of recent prevention efforts aimed at parents to postpone the alcohol use of their child at least until the age of 16. Future prevention programs should also target older age groups (i.e., age 16 years and older) and address the quantity of alcohol consumed by adolescents when they drink.

Do societal wealth, family affluence and gender account for trends in adolescent cannabis use? A 30 country cross-national study.

AIMS: To examine cross-national changes in frequent adolescent cannabis use (40+ times consumed over life-time at age 15) over time and relate these trends to societal wealth, family affluence and gender. DESIGN: Data from three cycles (2002, 2006, 2010) of the Health Behaviour in School-aged Children (HBSC) Study were used for cross-sectional and trend analyses of adolescent cannabis use. SETTING: Representative surveys in 30 European and North American countries. PARTICIPANTS: A total of 160 606 15-year-old students. MEASUREMENTS: Respondents' life-time cannabis use, demographics, family affluence (FAS) and frequency of peer contacts were measured individually. Indicators of wealth (gross domestic product per capita, GDP) and perceived availability of cannabis were obtained from national public data bases. FINDINGS: The frequency of life-time cannabis use decreased over time among adolescents in Europe and North America, particularly in western European countries and the United States (relative risk (RR) = 0.86: confidence interval (CI) 0.79-0.93). This trend was not observed consistently in rapidly developing countries in eastern, central and southern Europe. Over time (2002-10), cannabis use became: (i) less characteristic of high GDP countries in contrast to lower GDP countries (RR = 0.74: CI 0.57-0.95); (ii) less characteristic of youth from high FAS families in contrast to youth from low FAS families (RR = 0.83: CI 0.72-0.96); and (iii) characterized by an increasing gender gap, i.e. consumption was higher among males (RR 1.26: CI 1.04-1.53). Perceived availability of cannabis and peer contacts remained strong predictors of frequent cannabis use. CONCLUSIONS: Among 30 European and North American countries, cannabis use appears to have 'trickled down' over time, with developing countries taking on the former (heavier) use pattern of richer countries, and less affluent youth taking on the former (heavier) use pattern of more affluent youth. Cannabis use continues to be more common among adolescent males than females.