Young adolescent alcohol users drink at higher rates than their peers throughout adolescence and appear to be less amenable to intervention. This study compares those who reported alcohol use in the past year to those who reported no use in a multiethnic, urban sample of sixth graders in 61 schools in Chicago in 2002 (N = 4,150). Demographic, behavioral, intrapersonal, and socioenvironmental factors were identified based on behavioral theories and potential mediators of the Project Northland Chicago intervention. Single and multiple regression models were created for users and nonusers to determine associations between these factors and alcohol use behavior and intentions. The multiple regression models explained 35% and 56% of the variance in alcohol use behavior and intentions between students for nonusers and users, respectively. Results suggest that primary prevention programs for alcohol use should occur prior to sixth grade, particularly for the substantial group at high risk for early use.
alcohol use; adolescents; nonusers
The purpose of this study was to describe the extent to which vending offerings in 106 schools in the St. Paul-Minneapolis, Minnesota metropolitan area met criteria for types of beverages, fat and calories based on selected criteria offered by the Institute of Medicine.
Schools where youth participants were attending for the 2006-2007 school year were identified and invited to participate in the study (n=143); 81% of schools (n=116) agreed to participate.
Of the 116 schools, 106 had vending machines. Across schools with vending machines (n=106), 5085 food and 8442 beverage items were offered. Overall, only 18% of beverage items met criteria for calories and type of beverage; significantly more items in public schools met the criteria as compared to private schools (19% vs. 12%; p<0.01). This difference was also significant for high schools as compared to middle schools (18% vs. 22%; p<0.01). For food items, 41% met calorie criteria, 45% met fat criteria, and 22% met both fat and calorie criteria. Significantly more food items met both criteria in public than private schools (22% vs. 18%; p=0.01), while high schools (22%) and middle schools (21%) were similar. A very small proportion of foods (<5%) would have met the full criteria suggested by the Institute of Medicine for competitive foods..
Overall, foods and beverages offered in vending machines continue to be high in fat and calories. Public schools are doing a slightly better job of providing healthy foods as compared to private schools.
To determine whether alcohol use behaviors and alcohol-related consequences differed among students attending two-year versus four-year colleges.
Participants (N=13,700) from 7 two-year and 11 four-year colleges completed the 2010 College Student Health Survey. Alcohol use behaviors included past year alcohol use, past month alcohol use, and binge drinking over the past two weeks. Alcohol-related factors included average calculated blood alcohol level and average number of alcohol-related consequences. Cross-sectional mixed-effects regression analyses were conducted to determine if the prevalence of alcohol-related behaviors and consequences differed among two-year and four-year colleges.
Students attending four-year colleges, particularly males, were more likely to report past year alcohol use, past month alcohol use, and binge drinking, as well as a higher average blood alcohol content and a greater number of alcohol-related consequences than their two-year counterparts (p<0.05). Among female students there were fewer differences between two-year and four-year college students. Many differences remained after adjusting for socio-demographic factors (e.g., age, race/ethnicity), however, with the addition of living situation as a covariate, several of the differences among males were no longer significant.
Significant differences in alcohol-related behaviors and consequences exist among students attending two-year versus four-year colleges. While the prevalence of alcohol-related behaviors and consequences was lower among two-year college students, they are not a population to be over-looked. The prevalence of alcohol use remains high among both two-year and four-year college students, making it important for researchers to design appropriate interventions for all students regardless of the type of institution being attended.
Alcohol use; emerging adulthood; college youth
The purpose of this study was to explore how behavioral, intra-personal and socio-environmental factors were associated with the likelihood of having at least one older friend.
Participants included 3709 ethnically-diverse 8th grade students in the Project Northland Chicago intervention trial. Socio-demographic characteristics included gender, family composition, language spoken at home, race/ethnicity, and age. Behavioral factors included cigarette, alcohol, and marijuana use, depressed feelings, willingness to wear alcohol-branded merchandise, and violent and delinquent behavior. Intrapersonal factors included low refusal self efficacy and outcome expectations and expectancies. Socio-environmental factors included alcohol offers and access, normative estimates and expectations, and peer alcohol use. Having an older friend was defined as having at least one friend aged 16 or older (students’ mean age=14.2). Logistic mixed-effects regression models were used and controlled for gender, race/ethnicity, treatment status, and age.
Females and older eighth graders were significantly more likely to have at least one older friend. Students who scored higher on all of the behavioral, intra-personal and socio-environmental risk factors were significantly more likely to have at least one older friend. Significant gender interactions were found for several of the relationships.
Overall this study found multiple risk-related factors are associated with having older friends in eighth grade. Particularly important factors appear to be cigarette, marijuana and alcohol use, having friends who use alcohol, having increased alcohol offers, and being willing to wear or use alcohol-branded merchandise.
Peers; Friends; Risk Behaviors; Risk Factors; Adolescence
The purpose of this study was to determine if parents’ and children’s reports of parenting practices were correlated, if the reports were differentially associated with alcohol use, and which report had the strongest association with alcohol use.
Cross-sectional and longitudinal.
Public schools, Chicago, Illinois.
Participants included 1373 ethnically-diverse students and parents involved in an alcohol use prevention intervention. Surveys were conducted in sixth grade and eighth grade. Mixed-effects regression analyses were used to model relationships cross-sectionally and longitudinally.
Parents’ and children’s perceptions of parenting practices, while significantly correlated, were not strongly associated. Analyses within each parenting domain found parents’ report of parental monitoring and children’s reports of alcohol-specific communication, general communication, and relationship satisfaction were associated with alcohol use behaviors and intentions. After adjusting for all other parenting practices, parents’ report of parental monitoring and children’s report of alcohol-specific communication were most strongly related to alcohol use behaviors and intentions both cross-sectionally and longitudinally.
When comparing results across studies, it is important to identify whose report was used, parent or child, as the results may differ based on reporter. Studies with limited resources may consider using parents’ reports about parental monitoring and using children’s reports for alcohol-specific communication, general communication, and relationship satisfaction.
Parenting; parent-child relationships; alcohol use; early adolescence
The purpose of this study was to explore how exposure to alcohol outlets (around home and school) influenced alcohol use among 242 high-school students (mean age 16.4, 48.8% male, 93.4% White). Results found no relationship between alcohol outlet exposure, using a measure of both distance to and density around students’ homes and schools, and alcohol use. This study suggests that outlet exposure may not influence alcohol use among mostly White, middle- class, and suburban youth. However, the lack of association may also reflect the lower level of alcohol outlets present in low-density residential environments as well as differences in accessibility.
alcohol outlet density; adolescent alcohol use; alcohol outlet exposure
To examine cross-sectional and longitudinal associations between weight status and measures of risk and protective factors in youth.
Participants included 3010 students (72.1% white, 27.9% non-white), with a baseline mean age of 12.7 years from the Teens Eating for Energy and Nutrition at School (TEENS) study. Surveys were administered in seventh and eighth grade. Cross-sectional and longitudinal mixed-effects regression analyses were conducted to determine the association between body mass index z-score percentiles (BMI) and risk and protective factors (including substance use, depression, fighting, optimism, and spirituality).
Only depression was associated with BMI at the beginning of seventh grade. However, by the end of eighth grade, binge drinking, ATOD (alcohol, tobacco, and other drug) use, fighting, and depression were all cross-sectionally associated with BMI. Longitudinally, BMI in seventh grade did not predict risk and protective factors in eighth grade. However, ATOD use, fighting, depression, and optimism in seventh grade predicted BMI in eighth grade.
This study suggests there is a notable co-occurrence of unhealthy factors (including weight status, ATOD, depression) which appears to develop during the critical transition period through early adolescence. Specifically, earlier ATOD use, depression, increased fighting, and decreased optimism may lead to unhealthy increases in weight status, whereas early indicators of increased weight status do not appear to predict increases in these factors. This work yields important insights into the causal mechanisms underlying adolescent behavior patterning and the progression with which these unhealthy risk factor profiles are adopted during this critical age.
Obesity; risk and protective factors; substance use; depression
This study used eye-tracking technology to explore how individuals with different levels of health literacy visualize health-related information. The authors recruited 25 university administrative staff (more likely to have adequate health literacy skills) and 25 adults enrolled in an adult literacy program (more likely to have limited health literacy skills). The authors administered the Newest Vital Sign (NVS) health literacy assessment to each participant. The assessment involves having individuals answer questions about a nutrition label while viewing the label. The authors used computerized eye-tracking technology to measure the amount of time each participant spent fixing their view at nutrition label information that was relevant to the questions being asked and the amount of time they spent viewing nonrelevant information. Results showed that lower NVS scores were significantly associated with more time spent on information not relevant for answering the NVS items. This finding suggests that efforts to improve health literacy measurement should include the ability to differentiate not just between individuals who have difficulty interpreting and using health information, but also between those who have difficulty finding relevant information. In addition, this finding suggests that health education material should minimize the inclusion of nonrelevant information.
The goal of this group-randomized trial was to test the effectiveness of an adapted alcohol use preventive intervention for urban, low-income and multi-ethnic settings.
Design and Setting
Sixty-one public schools in Chicago were recruited to participate, were grouped into neighborhood study units, and randomly assigned to intervention or “delayed program” control condition.
The study sample (n=5812 students) was primarily African American, Hispanic and low-income.
Students, beginning in sixth grade (age 12), received three years of intervention strategies (curricula, family interventions, youth-led community service projects, community organizing).
Students participated in yearly classroom-based surveys to measure their alcohol use and related risk and protective factors. Additional evaluation components included a parent survey, a community leader survey, and alcohol purchase attempts.
Overall the intervention, compared with a control condition receiving “prevention as usual,” was not effective in reducing alcohol use, drug use or any hypothesized mediating variables (i.e., related risk and protective factors). There was a nonsignificant trend (p = .066) that suggested the ability to purchase alcohol by young appearing buyers was reduced in the intervention communities compared to the control communities, but this could be due to chance. Secondary outcome analyses to assess the effects of each intervention component indicated that the home-based programs were associated with reduced alcohol, marijuana, and tobacco use combined (p = .01), with alcohol use alone approaching statistical significance (p = .06).
Study results indicate the importance of conducting evaluations of previously validated programs in contexts that differ from the original study sample. Also, the findings highlight the need for further research with urban, low-income adolescents from different ethnic backgrounds to identify effective methods to prevent and reduce alcohol use.
alcohol prevention; urban youth; intervention adaptation
To investigate which points of the middle-school drinking distribution are the most influential in the social contagion of drinking across the middle-school years, in order to identify potential social multipliers.
We measured drinking intentions and behaviors by gender, school, and grade among urban middle-school students who participated in Project Northland Chicago in a longitudinal cohort design.
Individual drinking behaviors were consistently influenced by extreme (80th percentile) drinking intentions and behaviors. This effect was mediated through normal or average levels of drinking, over time.
Interventions can target extreme drinkers as the influential persons in middle-school grades.
social norms; drinking; middle school; gender; mediation
Despite the known deficits in sleep that occur during adolescence and the high prevalence of substance use behaviors among this group, relatively little research has explored how sleep and substance use may be causally related. The purpose of this study was to explore the longitudinal bi-directional relationships between sleep duration, sleep patterns and youth substance use behaviors. Participants included 704 mostly white (86.4 %) youth, 51 % female, with a baseline mean age of 14.7 years. Self-reported substance use behaviors included past month alcohol, cigarette, and marijuana use. Sleep measures included sleep duration on weekends and weekdays, total sleep, weekend oversleep, and weekend sleep delay. Cross-lagged structural equation models, accounting for clustering at the school level, were run to determine the longitudinal association between sleep and substance use adjusting for socio-demographic characteristics, pubertal status, body mass index z-score, and depressive symptoms. Cigarette use and weekend sleep were bi-directionally related as were marijuana use and total sleep. No other bidirectional associations were identified. However, alcohol use predicted shorter weekend oversleep and marijuana use predicted increased weekend sleep and weekend oversleep. Sleep patterns and duration also predicted adolescents’ cigarette, alcohol, and marijuana use. Sleep, both patterns and duration, and substance use among youth are intertwined. Future research is needed to explore these bidirectional relationships, as well as other important contextual factors that may moderate these associations.
Substance use; Sleep; Adolescents; Youth; Cross-lagged models
To determine the relationship between parent time demands and presence and enforcement of family rules and parent/child dyad weight status.
Dyads of one child/parent per family (n=681dyads), Twin Cities, Minnesota, 2007–2008 had measured height/weight and a survey of demographics, time demands and family rules-related questions. Parent/child dyads were classified into four healthy weight/overweight categories. Multivariate linear associations were analyzed with SAS, testing for interaction by work status and family composition (p<0.10).
In adjusted models, lack of family rules and difficulty with rule enforcement were statistically lower in dyads in which the parent/child was healthy weight compared to dyads in which the parent/child was both overweight (Difference in family rules scores=0.49, p=0.03; difference in rule enforcement scores=1.09, p=<0.01). Of parents who worked full-time, healthy weight dyads reported lower time demands than other dyads (Difference in time demands scores=1.44, p=0.01).
Family experiences of time demands and use of family rules are related to the weight status of parents and children within families.
adult; child; weight status; time demands; family rules
To investigate whether smoking prevalence in grade-level networks influences individual smoking, suggesting that peers are important social multipliers in teen smoking.
We measured gender-specific, grade-level recent and life-time smoking among urban middle-school students who participated in Project Northland Chicago in a longitudinal cohort design.
Within schools, grade-level recent smoking had comparable effects on girls’ and boys’ individual-level smoking. Grade-level lifetime smoking had a greater effect on girls’ smoking.
Interventions can target middle school classes and schools broadly, without making the identification of friendship networks a concern.
social norms; smoking; middle school; gender
Both substance use and obesity are prevalent among youth. As youth age, substance use rates increase and over the past three decades, obesity rates among youth have tripled. While these two factors have both short- and long-term health impacts, little research has explored how substance use and obesity among youth may be related. This study explores the bi-directional longitudinal relationships between substance use and body composition. Participants (N = 704; 50.7% female) were mostly white (86.4%) with a baseline mean age of 14.7 years. Objectively measured body composition was used to calculate body mass index z-scores (BMI z-score) and percent body fat. Cross-lagged structural equation models, accounting for clustering at the school level, were run to determine the longitudinal association between body composition and self-reported substance use (alcohol, cigarette, and marijuana), adjusting for socio-demographic characteristics, pubertal status, and weight satisfaction. Baseline alcohol use predicted decreased BMI z-score at follow-up and a similar association with percent body fat approached significance. Baseline cigarette use predicted increased percent body fat. No longitudinal associations were seen between baseline body composition and future substance use. Our results suggest that substance use contributes to subsequent body composition; however, body composition does not contribute to subsequent substance use. Continued research that explores these relationships longitudinally is greatly needed.
Body composition; Adolescents; Substance use; Obesity
To assess the relationship between adolescent perception of time to walk to neighborhood food retail outlets and purchasing of sugar sweetened beverages (SSB), fast and convenience food items and test for differences by urban versus suburban environment.
Cross-sectional observational study.
Twin Cities Metropolitan Area, Minnesota.
Adolescents from two studies completed survey-based measures on perceptions of time to walk to food retail outlets from home, purchasing patterns of SSB and fast and convenience store items, perceptions of personal safety and pedestrian infrastructure and demographic characteristics. Descriptive analysis, Spearman correlations and multivariate linear regression, accounting for clustering, were conducted using SAS.
There were 634 adolescents, approximately half male, predominately white, with a middle-class background. Greater perceived time to food outlets were associated with less frequent purchasing of SSB, convenience store foods and fast food items. Multivariate models showed that a perceived shorter walking time (i.e. 1–5 versus 31+ minutes) was significantly associated with more SSB purchasing. SSB purchases were also significantly associated with the number of food outlets within a 10–minute walk (B=0.05, p=0.02).
A reduction in consumption of SSB and other energy dense snacks is an important obesity prevention approach. An approach offering alternatives or reducing exposure in addition to education to alter purchasing habits may contribute to improving dietary habits and reducing the obesity epidemic.
Information regarding associations between types of away-from-home family meal sources and obesity and other chronic diseases could help guide dietitians. The present study describes the purchase frequency of away-from-home food sources for family dinner (fast food, other restaurant purchases, home delivery, and take-out foods) and associations with weight status and percent body fat among adolescents (n=723) and parents (n=723) and related biomarkers of chronic disease among adolescents (n=367). A cross-sectional study design was used with baseline parent surveys and anthropometry/fasting blood samples from two community-based obesity studies (2006–2008) in Minnesota. Logistic regression and general linear modeling assessed associations between frequency of family dinner sources (weekly versus none in past week) and outcomes (parent and adolescent overweight/obesity and percent body fat; adolescent metabolic risk cluster z-score (MRC), cholesterol, HDL-C, LDL, triglycerides, fasting glucose, insulin and systolic blood pressure. Models accounted for clustering and adjusted for study allocation, baseline meal frequency and demographic characteristics. The odds of overweight/obesity were significantly greater when families reported at least one away-from-home dinner purchase in the past week (OR=1.2–2.6). Mean percent body fat, MRC z-scores and insulin levels were significantly greater with weekly purchases of family dinner from fast food restaurants (p’s < .05). Mean percent body fat, MRC z-scores and HDL levels were significantly higher for families who purchased weekly family dinner from take-out sources (p’s < .05). Although frequent family dinners may be beneficial for adolescents, the source of dinners is likely as important in maintaining a healthy weight. Interventions should focus on encouragement of healthful family meals.
family dinner; overweight; obesity; away-from-home; adolescents
To examine associations between weight misperception and youth health risk and protective factors.
Three thousand ten US seventh-graders (72.1% white, mean age: 12.7 years) self-reported height, weight, risk, and projective factors. Analyses were conducted to determine cross-sectional and longitudinal associations between weight overestimation and health risk and protective factors.
Risk and protective factors had significant cross-sectional associations with weight overestimation. However, only depressive symptoms and reduced optimism predicted weight overestimation in eighth grade. Weight overestimation did not predict engagement in risky behaviors.
Weight overestimation and risk factors appear to co-occur, suggesting a constellation of risk that warrants further research.
weight perception; risk and protective factors; substance use; depression
Obesity may cluster in families due to shared physical and social environments.
This study aims to identify family typologies of obesity risk based on family environments.
Using 2007–2008 data from 706 parent/youth dyads in Minnesota, we applied latent profile analysis and general linear models to evaluate associations between family typologies and body mass index (BMI) of youth and parents.
Three typologies described most families with 18.8% “Unenriched/Obesogenic,” 16.9% “Risky Consumer,” and 64.3% “Healthy Consumer/Salutogenic.” After adjustment for demographic and socioeconomic factors, parent BMI and youth BMI Z-scores were higher in unenriched/obesogenic families (BMI difference=2.7, p<0.01 and BMI Z-score difference=0.51, p<0.01, respectively) relative to the healthy consumer/salutogenic typology. In contrast, parent BMI and youth BMI Z-scores were similar in the risky consumer families relative to those in healthy consumer/salutogenic type.
We can identify family types differing in obesity risks with implications for public health interventions.
Latent profile analysis; Family types; Youth; Obesogenic environment
The objective of this study was to determine whether obesity prevalence and weight-related behaviors (e.g., diet, physical activity) differ among students enrolled in two-year community/technical colleges and those attending four-year colleges/universities. This information could inform the development of intervention strategies. Through an existing surveillance system of Minnesota post-secondary education institutions, survey data were collected from 16,539 students from 27 campuses (14 two-year college campuses, 13 four-year college/university campuses; 2007-2008), including self-reported physical activity, media use, dietary patterns, weight control behaviors, height and weight. Unadjusted analyses indicated that students enrolled in two-year colleges, particularly females, had a higher prevalence of overweight/obesity, lower levels of physical activity, more television viewing, higher intakes of soda, fast food, and diet pills compared to students attending four-year colleges (p<0.05). Females attending four-year colleges were more likely to engage in certain unhealthy weight control behaviors (taking diet pills, binge eating, self-induced vomiting) compared to females attending two-year institutions. Among male students there were fewer differences between two-year and four-year colleges. Controlling for sociodemographic factors (e.g., race/ethnicity, age), most disparities in prevalence estimates remained, though many were attenuated. Overall, few young adults engage in weight-related behaviors consistent with national recommendations. Two-year college students may represent a particularly at-risk group. Disparities between two- and four-year college students exist beyond the sociodemographic differences in these populations. Effective weight-related interventions are needed for young adults, particularly females attending two-year colleges and all males attending post-secondary institutions.
To assess the correlates of parental classification of adolescent weight status.
Measured adolescent weight status was compared to parent self-report perception data (n=374 dyads) using multivariate analyses with interactions to identify characteristics associated with inaccurate parent classification of adolescent weight status.
Adolescent weight status was underestimated by 31% of parents. College-educated parents were more likely to underestimate the weight of their male adolescents (OR=1.95) and overweight adolescents (OR=4.0). Non-college-educated parents were 8.92 times as likely to misclassify overweight adolescents, regardless of the sex of the child.
Parental perception may play a role in supporting adolescent’s healthy weight-related behaviors.
parent perceptions; adolescent weight; overweight; underestimate; weight discordance
Research to date in young children and adults shows a strong, inverse relationship between sleep duration and risk for overweight and obesity. Fewer studies examining this relationship have been conducted in adolescents. The purpose of the article is to describe the relationship between sleep and weight in a population of adolescents, controlling for demographics, energy intake, energy expenditure, and depression. This is a cross-sectional study of 723 adolescents participating in population-based studies of the etiologic factors related to obesity. We examined the relationship between three weight-related dependent variables obtained through a clinical assessment and three sleep variables obtained through self-report. Average caloric intake from dietary recalls, average activity counts based on accelerometers, and depression were included as covariates and the analysis was stratified by gender and grade level. Our results show that the relationship between sleep duration and BMI is evident in middle-school boys (β = −0.32, s.e. = 0.06: P < 0.001) and girls (β = −0.18, s.e. = 0.08: P = 0.02) but largely absent in high-school students. Differences in sleep patterns have little association with weight in males, but in high-school girls, waking up late on weekends as compared to weekdays is associated with lower body fat (β = −0.80, s.e. = 0.40: P = 0.05) and a healthy weight status (β = −0.28, s.e. = 0.14: P = 0.05). This study adds to the evidence that, particularly for middle-school boys and girls, inadequate sleep is a risk factor for early adolescent obesity. Future research needs to examine the relationship longitudinally and to study potential mediators of the relationship.
To examine neighbourhood food environments, adolescent nutrition and weight status.
Cross-sectional, observational study.
Minneapolis/St. Paul metropolitan region, Minnesota, USA.
A total of 349 adolescents were recruited to the study. Participants completed 24 h dietary recalls and had their weight and height measured. They also reported demographic information and other diet-related behaviours. Geographic Information Systems were used to examine the availability and proximity of food outlets, particularly those captured within the 800, 1600 and/or 3000m network buffers around participants' homes and schools.
Adjusting for gender, age and socio-economic status, adolescents' sugar-sweetened beverage intake was associated with residential proximity to restaurants (including fast food), convenience stores, grocery stores and other retail facilities within the 800 and/or 1600m residential buffers (P ≤ 0.01). BMI Z-score and percentage body fat were positively associated with the presence of a convenience store within a 1600m buffer. Other individual-level factors, such as energy, fruit and vegetable intake, as well as convenience store and fast food purchasing, were not significantly associated with features of the residential neighbourhood food environment in adjusted models. In addition, school neighbourhood environments yielded few associations with adolescent outcomes.
Many factors are likely to have an important role in influencing adolescent dietary intake and weight status. Interventions aimed at increasing neighbourhood access to healthy foods, as well as other approaches, are needed.
Adolescent; Food environment; Obesity
Growth curve models examined changes in adolescent self-reported parent-child communication conditional on family meal frequency over a 3.5 year period among a population of racially-diverse, low-income adolescents from an urban environment (n = 4750). Results indicated that although both family dinner frequency and adolescent perceptions of parent-child communication scores were characterized by negative linear growth over time (both p < .0001), family dinner frequency was positively associated with adolescent perceptions of parent-child communication scores over time (p < .0001). Study findings suggest that families with teenagers may enhance parent-child communication and ultimately promote healthy adolescent development by making family dinner a priority. Additionally, the communication benefits of family dinner at the beginning of 6th grade may be protective through 8th grade.
adolescents; family dinner; family meals; parent-child communication; race/ethnicity; urban
To explore how weekday and weekend sleep patterns are related to adolescent substance use, depressive symptoms, and school truancy.
Self-report surveys of 242 youth (93.4% white, mean age 16.4 years).
Longer weekday sleep duration was inversely associated with depressive symptoms, past month alcohol use, and drunkenness. Later weekend bedtime and wake-times, compared to those of weekdays, were associated with increased substance use and truancy.
Weekday sleep duration appears to be protective for substance use, depression and school truancy for teenagers. However, inconsistent sleep patterns between weekdays and weekends were associated with a range of markers for adolescent risk.
adolescents; sleep; risk behaviors; depressive symptoms