Alfgeir L. Kristjansson

Health Behavior and Academic Achievement Among Adolescents: The Relative Contribution of Dietary Habits, Physical Activity, Body Mass Index, and Self-Esteem

This study tested a structural equation model to estimate the relationship between health behaviors, body mass index (BMI), and self-esteem and the academic achievement of adolescents. The authors analyzed survey data from the 2000 study of Youth in Iceland , a population-based, cross-sectional sample of 6,346 adolescents in Iceland. The model demonstrated good fit with chi-square of 2685 (n = 5,810, df = 180), p < .001, Comparative Fit Index value of .94, and a root mean square error of approximation of .049. Lower BMI, physical activity, and good dietary habits were all associated with higher academic achievement; however, health behavior was positively and robustly associated with greater self-esteem. Self-esteem was positively influenced both through physical activity (β = .16) and the consumption of fruits and vegetables (β = .14). In contrast, poor dietary habits negatively influenced self-esteem and academic achievement, and self-esteem was negatively influenced by increasing levels of BMI (β = —.05).

Adolescent substance use, sleep, and academic achievement: evidence of harm due to caffeine.

Using academic achievement as the key outcome variable, 7377 Icelandic adolescents were surveyed for cigarette smoking, alcohol use, daytime sleepiness, caffeine use, and potential confounders. Structural equation modeling (SEM) was used to examine direct and indirect effects of measured and latent variables in two models: the first with caffeine excluded and the second with caffeine included. A substantial proportion of variance in academic achievement, which might otherwise have been attributed to the harmful effects of cigarette smoking and alcohol use, was found to be attributable to caffeine. Evidence was obtained that daytime sleepiness, which was found to be independently associated with usage of licit substances (nicotine and alcohol) and caffeine, may be an important mediator of the negative impact of those substances on academic achievement. Findings suggest the importance of including measurements of caffeine consumption in future studies of adolescent substance use.

Substance use prevention for adolescents: the Icelandic Model

Data from the European School Survey Project on Alcohol and other Drugs have shown that adolescent substance use is a growing problem in western and particularly Eastern European countries. This paper describes the development, implementation and results of the Icelandic Model of Adolescent Substance Use Prevention. The Icelandic Model is a theoretically grounded, evidence-based approach to community adolescent substance use prevention that has grown out of collaboration between policy makers, behavioural scientists, field-based practitioners and community residents in Iceland. The intervention focuses on reducing known risk factors for substance use, while strengthening a broad range of parental, school and community protective factors. Annual cross-sectional surveys demonstrate the impact of the intervention on substance use among the population of 14- to 16-year-old Icelandic adolescents. The annual data from two cohorts of over 7000 adolescents (>81% response rate) show that the proportions of those who reported being drunk during the last 30 days, smoking one cigarette or more per day and having tried hashish once all declined steadily from 1997 to 2007. The proportions of adolescents who reported spending time with their parents and that their parents knew with whom they were spending their time increased substantially. Other community protective factors also showed positive changes. Although these data suggest that this adolescent substance use prevention approach successfully strengthened a broad range of parental, school and community protective factors, the evidence of its impact on reducing substance use needs to be considered in light of the correlational data on which these observations are based.

Trends in physical activity and participation in sports clubs among Icelandic adolescents

BACKGROUND Physical activity among adolescents and its implications for health status is of increasing concern. We examined trends in physical activity and participation in sports clubs among Icelandic adolescents. METHODS Cross-sectional survey data were used to determine levels of vigorous physical activity and participation in sports clubs (defined as engaging in moderately intensive activity four times or more a week) for cohorts of Icelandic adolescents in 1992, 1997, 2000 and 2006. RESULTS There was a 6% increase in the rate of vigorous physical activity and a 15% increase in active sports club participation among 14- and 15-year old Icelandic adolescents from 1992 to 2006. The trends were consistent across genders; however, only 53% of boys actually achieved the recommended criterion for vigorous physical activity, with the percentage of girls averaging 16% lower than that for boys. Additionally, there was an overall increase in the proportion of inactive adolescents, with girls consistently reporting higher levels of inactivity than boys even though the net increase in inactivity was higher for boys. CONCLUSION Although our results show an overall increase in vigorous physical activity and participation in sports clubs over the past decade among both genders, our data also indicate that over half of all Icelandic adolescents are not achieving the recommended level of participation in physical activity. Furthermore, less than one third of the population studied is achieving the recommended level of activity through organized clubs. Initiatives to increase physical activity among the least active of adolescents should receive high priority in public health.

Parental divorce and adolescent cigarette smoking and alcohol use: assessing the importance of family conflict

Aim: To investigate how family conflict contributes to the relationship between parental divorce and adolescent cigarette smoking and alcohol use.

Perceived parental reactions and peer respect as predictors of adolescent cigarette smoking and alcohol use.

Cigarette smoking and alcohol use contribute substantially to the global burden of morbidity and premature mortality. Most use begins during adolescence, often with experimentation taking place between 11 and 15 years of age. This study examined the importance of perceived parental reactions to, and peer respect for, cigarette smoking and alcohol use. Particular attention was given to the relative importance of these variables compared with the more widely examined influences of perceived parental and peer support. Our final models explained 44% of the variance in cigarette smoking and 46% in alcohol use. Most of the explained variance in both cigarette smoking and alcohol use was accounted for by only three variables: peer use, perceived parental reaction to use, and perceived respect from peers if using. Our findings indicate that perceived parental reaction to use and peer respect for use may be important contributors to adolescent cigarette smoking and alcohol use.

Adolescent substance use, parental monitoring, and leisure-time activities: 12-year outcomes of primary prevention in Iceland

OBJECTIVE To examine 12-year changes in alcohol use and cigarette smoking in response to community-based prevention activities among Icelandic adolescents. METHODS This study used a quasi-experimental, non-randomized control group design to compare outcomes in 4 Icelandic communities (n=3117) that participated in community-based substance use prevention activities designed to increase levels of parental monitoring and adolescent engagement in healthy leisure-time activities and a matched group of 7 comparison communities (n=1,907). Annual, nationwide, population-based cross-sectional surveys of the prevalence of adolescent substance use were conducted among cohorts of Icelandic adolescents, aged 14-15 years (N=5,024), in all communities from 1997 to 2009. RESULTS Parental monitoring and adolescent participation in organized sports increased in communities that adopted the intervention program compared to communities that did not, whereas unmonitored idle hours and attendance at unsupervised parties decreased. Over time, alcohol use (OR=0.89, 95% CI 0.82, 0.98, p=0.012) and being intoxicated during the last 30 days (OR=0.86, 95% CI 0.78, 0.96, p=0.004) decreased more in the intervention than control communities. CONCLUSION Community-based prevention designed to strengthen parental monitoring and participation in organized sports may confer some protection against adolescent substance use.

Adolescent health behavior, contentment in school, and academic achievement.

OBJECTIVES To examine the association between health behavior indicators, school contentment, and academic achievement. METHODS Structural equation modeling with 5810 adolescents. RESULTS Our model explained 36% of the variance in academic achievement and 24% in school contentment. BMI and sedentary lifestyle were negatively related to school contentment and academic achievement, but physical activity was positively related to school contentment and academic achievement (P < .01). School contentment was strongly related to academic achievement but only a weak mediator of the health behavior indicators. CONCLUSION Findings may inform the efforts to improve academic achievement and the general health status of youth.

The Role of Parental Support, Parental Monitoring, and Time Spent With Parents in Adolescent Academic Achievement in Iceland: A Structural Model of Gender Differences

This study examines the relationship between parental support, parental monitoring, and time spent with parents and academic achievement among adolescent girls and boys in Iceland, a high‐income per‐capita Nordic country. The indirect role of school effort is also examined. Data of 7430 9th and 10th graders is analyzed in the study. Structural equation models show that parental factors are all associated with academic achievement among both boys and girls. However, for both genders, these associations are mostly indirect, through school effort. The relationship between the parental factors and academic achievement is similar in strength for boys and girls. Boys however receive less parental support and are less monitored than girls. Study implications are discussed.

Data collection procedures for school-based surveys among adolescents: the Youth in Europe Study

BACKGROUND Collection of valid and reliable surveillance data as a basis for school health promotion and education policy and practice for children and adolescence is of great importance. However, numerous methodological and practical problems arise in the planning and collection of such survey data that need to be resolved in order to ensure the validity of the data and to maximize the response rate without being prohibitively costly. METHOD This article builds on a 15-yearlong experience of such annual data collections in Iceland and describes the preparation, process, and collection of data that provide a common methodologic framework for the school-based survey, Youth in Europe, a population-based survey of 14- to 16-year-old adolescents, being collected across 18 European cities now participating in the European Cities Against Drugs (ECAD) program. RESULTS We identified 11 critical steps for developing and implementing the surveys in light of the recent literature on the preparation and implementation practices in school-based data collection among adolescents. CONCLUSION Limiting the disruption of daily operations in schools while at the same time ensuring both quality and clarity of data collection procedures in school-based surveys are of paramount importance for researchers, school personnel, and students.