Preliminary impact of the adoption of the Icelandic Prevention Model in Tarragona City, 2015-2019: A repeated cross-sectional study.

Background: There is a great need for effective primary prevention intervention strategies to reduce and delay onset of adolescent substance use. The Icelandic Prevention Model (IPM) showed great success in Iceland over the past twenty plus years, however, evidence for the transferability of model is still somewhat limited. Using data collected in Tarragona during regional efforts to begin adoption of the IPM in Catalonia, this study tested the transferability and stability of the core risk and protective factor assumptions of the IPM overtime and examined trends of lifetime smoking, e-cigarette-use, alcohol-use, intoxication, and cannabis-use within the same time period. Methods: This study includes responses from 15- to 16-years-olds from two region-wide samples taken in 2015 and 2019 in Tarragona (N = 2,867). Survey questions assessed frequency of lifetime: smoking, e-cigarette-use, alcohol-use, intoxication, and cannabis-use, and the core model assumptions. Demographic data were also collected. Logistic regression models of main effects with and without time interaction were used to test assumptions and their stability across time. Chi-square tests and Wilcoxon-Mann-Whitney U tests were used to compare prevalence of substance use and mean scores of primary prevention variables respectively. Results: Lifetime: smoking (-7%, p < 0.001) and cannabis-use (-4%, p < 0.001) decreased, and e-cigarette-use increased (+33%, p < 0.001) in Tarragona. Lifetime intoxication (-7%, p < 0.001) decreased in a single zone exclusively. Most core model assumptions held in their hypothesised direction across time. The strongest positive association was observed between time spent with parents during weekends and reduced odds of lifetime smoking (OR: 0.62, 95%CI: 0.57-0.67) and the strongest negative association was observed between being outside after midnight and increased odds of lifetime intoxication (OR: 1.41, 95%CI: 1.32-1.51). Mean scores of primary prevention variables also changed disproportionately in Tarragona. Conclusion: This study confirms that the core IPM assumptions are similar in Tarragona as in Iceland and other contexts previously examined. They also indicate that prevalence of lifetime smoking, intoxication, and cannabis-use decreased disproportionately in Tarragona between 2015 and 2019 during the first phase of regional adoption of the model. Thus, targeting model assumptions represents a viable primary prevention strategy for communities that hope to reduce smoking, alcohol-use, intoxication, and cannabis-use among adolescents.

Depressive symptoms, mental wellbeing, and substance use among adolescents before and during the COVID-19 pandemic in Iceland: a longitudinal, population-based study.

BACKGROUND: Adolescence represents a crucial developmental period in shaping mental health trajectories. In this study, we investigated the effect of the COVID-19 pandemic on mental health and substance use during this sensitive developmental stage. METHODS: In this longitudinal, population-based study, surveys were administered to a nationwide sample of 13-18-year-olds in Iceland in October or February in 2016 and 2018, and in October, 2020 (during the COVID-19 pandemic). The surveys assessed depressive symptoms with the Symptom Checklist-90, mental wellbeing with the Short Warwick Edinburgh Mental Wellbeing Scale, and the frequency of cigarette smoking, e-cigarette use, and alcohol intoxication. Demographic data were collected, which included language spoken at home although not ethnicity data. We used mixed effects models to study the effect of gender, age, and survey year on trends in mental health outcomes. FINDINGS: 59 701 survey responses were included; response rates ranged from 63% to 86%. An increase in depressive symptoms (ß 0·57, 95% CI 0·53 to 0·60) and worsened mental wellbeing (ß -0·46, 95% CI -0·49 to -0·42) were observed across all age groups during the pandemic compared with same-aged peers before COVID-19. These outcomes were significantly worse in adolescent girls compared with boys (ß 4·16, 95% CI 4·05 to 4·28, and ß -1·13, 95% CI -1·23 to -1·03, respectively). Cigarette smoking (OR 2·61, 95% CI 2·59 to 2·66), e-cigarette use (OR 2·61, 95% CI 2·59 to 2·64), and alcohol intoxication (OR 2·59, 95% CI 2·56 to 2·64) declined among 15-18-year-olds during COVID-19, with no similar gender differences. INTERPRETATION: Our results suggest that COVID-19 has significantly impaired adolescent mental health. However, the decrease observed in substance use during the pandemic might be an unintended benefit of isolation, and might serve as a protective factor against future substance use disorders and dependence. Population-level prevention efforts, especially for girls, are warranted. FUNDING: Icelandic Research Fund. TRANSLATION: For the Icelandic translation of the abstract see Supplementary Materials section.

Testing risk and protective factor assumptions in the Icelandic model of adolescent substance use prevention.

Iceland has witnessed a dramatic decline in adolescent substance use that may be partly the result of efforts related to the Icelandic prevention model (IPM). We sought to test risk and protective factor assumptions of the IPM using a prospective cohort study with 12 months separating baseline from follow-up. Participants were students in grades 8 and 9 in the national Icelandic school system enrolled in the spring of 2018 and 2019 (N=2165). Participants self-reported their experiences of cigarette smoking, alcohol consumption, and cannabis use and seven risk and protective factors. Analyses were conducted with generalized linear modeling with extension to general estimating equations with correlated outcomes data. Both individual main-effects models and collective models including all main-effects were tested. Out of 28 individual main-effects models, 23 produced findings consistent with study premises (P<0.05). Multiple main-effects models largely sustained the findings of the individual main-effects models. Findings support the assumption that the risk and protective factors commonly emphasized in the IPM are associated with the four different substance use outcomes in the hypothesized direction. Communities that plan to implement the IPM among adolescents might consider these factors in their work.

Trends in substance use and primary prevention variables among adolescents in Lithuania, 2006-19.

BACKGROUND: Since the implementation of the Icelandic Model for Primary Prevention of Substance Use in Iceland (IPM), substance use has decreased steadily among 14-16-year-old adolescents and primary prevention factors have improved. Although the IPM is being implemented in several other regions around the world, information documenting its effectiveness in other country contexts is lacking. This study assessed trends in substance use and primary prevention variables in three cities in Lithuania following the implementation of the IPM. METHODS: Data collected from repeated, comparative cross-sectional self-report surveys conducted among a total of 30 572 10th graders in the cities of Kaunas, Klaipeda and Vilnius, Lithuania, from 2006 to 2019, were analyzed. Cochran-Armitage test for linear trend and analysis of variance for linear trend was used to assess time-trends in prevalence of substance use and mean levels of primary prevention variables over time. RESULTS: Following the implementation of IPM rates of cigarette smoking and the use of alcohol, cannabis and amphetamine has decreased among 10th graders in Lithuania's three largest cities and simultaneously preventive variables targeted have improved. Similar to Iceland, primary prevention variables were related to substance use in the expected direction, with the exception of organized sports participation, which was not associated with less likelihood of alcohol, cannabis and amphetamine use. CONCLUSION: Trends in substance use and primary prevention variables following the implementation of the IPM are similar in the three cities in Lithuania as in Iceland. Further research is needed to better understand the mechanisms underlying these trends.

A multi-level developmental approach towards understanding adolescent mental health and behaviour: rationale, design and methods of the LIFECOURSE study in Iceland.

PURPOSE: Identifying and understanding modifiable risk and protective factors that can inform early detection and intervention to prevent adolescent emotional problems and harmful behaviours is among the most pressing modern-day public health challenges. This paper describes the rationale, objectives, methods, and anticipated outcomes of the LIFECOURSE study, a multi-level, bio-psychosocial prospective study designed to advance our understanding of factors that shape adolescent mental health and behaviour. METHODS: Conducted by the Icelandic Centre for Social Research and Analysis at Reykjavik University, LIFECOURSE is a longitudinal population-based developmental study of Icelandic adolescents born in 2004. The study utilizes a comprehensive multi-informant assessment of individual, societal and biological factors measured across the lifespan. Data assembly and collection were conducted from 2016-2020 and utilize both retrospective and prospective data sources: (a) retrospective registry data assembled from seven national databases, (b) prospectively collected social surveys and (c) biomarker samples. RESULTS: Of the 3914 eligible adolescents, 60.8% (n = 2378) provided informed parental consent and student assent to participate in the study, with approximately half of the participants being female (n = 1175, 49.4%) and the majority being born in the capital area (n = 1455; 61.2%). The coverage of available data from the national databases and participation in the social surveys ranged from 81.7 to 100%. CONCLUSIONS: Major gaps remain in our knowledge of how individual, societal and biological factors across the lifespan-from early life to adolescence-interact and shape the risk for emotional problems and harmful behaviours during adolescence. The LIFECOURSE study was designed to address this knowledge gap.

Development and Guiding Principles of the Icelandic Model for Preventing Adolescent Substance Use.

Adolescent substance use-the consumption of alcohol, tobacco, and other harmful drugs-remains a persistent global problem and has presented ongoing challenges for public health authorities and society. In response to the high rates of adolescent substance use during the 1990s, Iceland has pioneered in the development of the Icelandic Model for Primary Prevention of Substance Use-a theory-based approach that has demonstrated effectiveness in reducing substance use in Iceland over the past 20 years. In an effort to document our approach and inform potentially replicable practice-based processes for implementation in other country settings, we outline in a two-part series of articles the background and theory, guiding principles of the approach, and the core steps used in the successful implementation of the model. In this article, we describe the background context, theoretical orientation, and development of the approach and briefly review published evaluation findings. In addition, we present the five guiding principles that underlie the Icelandic Prevention Model's approach to adolescent substance use prevention and discuss the accumulated evidence that supports effectiveness of the model. In a subsequent Part 2 article, we will identify and describe key processes and the 10 core steps of effective practice-based implementation of the model.

Implementing the Icelandic Model for Preventing Adolescent Substance Use.

This is the second in a two-part series of articles about the Icelandic Model for Primary Prevention of Substance Use (IPM) in this volume of Health Promotion Practice. IPM is a community collaborative approach that has demonstrated remarkable effectiveness in reducing substance use initiation among youth in Iceland over the past 20 years. While the first article focused attention on the background context, theoretical orientation, evaluation and evidence of effectiveness, and the five guiding principles of the model, this second article describes the 10 core steps to practical implementation. Steps 1 to 3 focus on building and maintaining community capacity for model implementation. Steps 4 to 6 focus on implementing a rigorous system of data collection, processing, dissemination, and translation of findings. Steps 7 to 9 are designed to focus community attention and to maximize community engagement in creating and sustaining a social environment in which young people become progressively less likely to engage in substance use, including demonstrative examples from Iceland. And Step 10 focuses on the iterative, repetitive, and long-term nature of the IPM and describes a predictable arc of implementation-related opportunities and challenges. The article is concluded with a brief discussion about potential variation in community factors for implementation.

Do population trends in adolescent electronic cigarette use coincide with changes in prevalence of cigarette smoking?

Adolescents who initiate electronic cigarette (EC) use without having ever used tobacco are more likely than those that have not initiated EC use to try cigarette smoking over time. However, whether rates of EC use coincide with cigarette smoking rates at the population level remains unknown. This study aimed to compare trends in ever, current, and daily use of EC and cigarette smoking among adolescents in Iceland from 2015 to 2018. We analyzed four waves of pooled cross-sectional population-based school survey data with students enrolled in the 8th, 9th and 10th grades in the national Icelandic school system (n = 42,440, boys = 50.1%). Response rates ranged between 83.3% and 86.0%. Findings for 8th, 9th, and 10th grade students, and the combined sample, revealed a consistent pattern: prevalence of cigarette smoking either remained unchanged or decreased minimally over the study period. In the combined sample rates of ever smoking remained between 9 and 10% during the entire study period, whereas the prevalence of daily cigarette smoking was around 1%. The use of EC increased 2- to 3-fold in all age groups. Ever use increased from 12% to roughly 30% in the combined group and daily use increased from about 2% to 6% during the same period. We conclude that the prevalence of adolescent cigarette smoking in Iceland remained mostly unchanged between the years 2015 and 2018, whereas EC use increased exponentially during the same period. The prevalence of EC use now far outweighs cigarette smoking in 8th-10th grade youth in Iceland.

Population trends in smoking, alcohol use and primary prevention variables among adolescents in Iceland, 1997-2014.

AIMS: To estimate linear time-trends in substance use and primary prevention variables in adolescents in Iceland from 1997 to 2014. DESIGN: Repeated, cross-sectional population-based school surveys with seven waves of pooled data. SETTING: Iceland. PARTICIPANTS: All accessible students enrolled in the 9th and 10th grades in the national Icelandic school system during the spring of 1997, 2000, 2003, 2006, 2009, 2012 and 2014 (n = 50 412, boys = 50%). Response rates ranged between 81 and 90% of the population. MEASUREMENTS: Measures on substance use included smoking and alcohol use. Primary prevention measures included parental monitoring, parental social involvement, participation in organized sports and reduced participation in a party life-style. FINDINGS: Substance use decreased consistently during the study period. For example, 30-day drunkenness declined from 29.6 in 1997 to 3.6% in 2014 (linear trend: χ(2) (1)  = 2846.8, P < 0.001), and daily smoking during the last 30 days declined from 17.0 to 1.6% during the same period (linear trend: χ(2) (1)  = 1614.3, P < 0.001). Primary prevention factors strengthened over time. For example, the mean score for parents knowing where their children are in the evenings rose from 2.44 in 1997 to 3.08 in 2014 (Ftrend(1, 42635) , 2538.3, P < 0.001), and mean scores for participation in party life-style declined from 2.23 in 1997 to 1.71 in 2014 (Ftrend(1, 38773) , 2033.1, P < .001). CONCLUSIONS: Substance use among adolescents in Iceland has declined steadily from 1997 to 2014, while primary prevention factors for substance use have increased in strength during the same time-period.

Self-generated identification codes in longitudinal prevention research with adolescents: a pilot study of matched and unmatched subjects.

Self-generated identification codes (SGICs) are an increasingly utilized methodological feature of longitudinal prevention research among adolescents. This study sought to test the differences between the matched and unmatched groups at baseline on a number of background, health, and well-being and risk behavior measures in a prevention study among 13- to 16-year-old Icelandic adolescents where a SGIC was constructed and used to link individual-level respondent data over two data collection points one year apart. We use pilot data from two Reykjavik city secondary schools collected as part of the population study Youth in Iceland in February 2010 and 2011 (N = 366, SGIC matching rate 61%). Baseline results for the matched and unmatched participants are compared. Findings indicate that the unmatched subjects are both more likely to be substance users than their matched counterparts as well as being more likely to be boys and/or from disrupted families. Five out of the seven scaled measures for risk and protective factors and personality indicators reveal no difference between the matched and unmatched subjects and the significantly different measures reveal small effect sizes between the two groups. However, the effect sizes for substance use are significantly different between the matched and unmatched groups for all seven substance use measures with effect sizes from 0.52 to 1.32. These findings therefore indicate that the measurement validity of adolescent risk behaviors such as substance use may be put in jeopardy when using SGIC and that unmatched subjects may be more likely to distrust the SGIC process.

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.