Effectiveness of the "Smoke-Free Class Competition" in delaying the onset of smoking in adolescence

Behavioral Economics and Tobacco Control: Current Practices and Future Opportunities

Despite considerable progress, smoking remains the leading preventable cause of death in the United States. To address the considerable health and economic burden of tobacco use, the development of improved tobacco control and treatment interventions is critical. By combining elements of economics and psychology, behavioral economics provides a framework for novel solutions to treat smokers who have failed to quit with traditional smoking cessation interventions. The full range of behavioral economic principles, however, have not been widely utilized in the realm of tobacco control and treatment. Given the need for improved tobacco control and treatment, the limited use of other behavioral economic principles represents a substantial missed opportunity. For this reason, we sought to describe the principles of behavioral economics as they relate to tobacco control, highlight potential gaps in the behavioral economics tobacco research literature, and provide examples of potential interventions that use each principle.

The Effect of a "Class Smoke Free Pledge" on Breath Carbon Monoxide in Arabic Male Adolescents

Introduction

Arabic male adolescents have a high smoking prevalence. Introduction of "Class smoke-free" pledges have been successful amongst European adolescents but have not been evaluated using objective valid measures. We tested the impact of adding a smoke free pledge strategy to a proven peer-led asthma and smoking prevention program on breath carbon monoxide level (BCO) in male high-school students in Jordan.

Methods

We enrolled male students from four high-schools in Irbid, Jordan. Schools were randomly assigned to receive either TAJ (Triple A in Jordan, n = 218) or TAJ-Plus (with added class smoke-free pledge, n = 215). We hypothesized that students receiving TAJ-Plus would have greater reduction in BCO levels than those only receiving the TAJ intervention. Asthma and smoking status were assessed by self-administered questionnaires. Smoking outcomes were collected using a BCO Monitor.

Results

Both groups had significant reductions in BCO levels post-intervention (p < .0001), however, decreases were greater in TAJ-Plus group (3.9 ± 0.2 vs. 4.8 ± 0.2, p < .0001). Intervention effects on BCO over time did not vary by smoking status (p = .085), asthma status (p = .602), or a combination of the two (p = .702).

Conclusions

An added smoke-free pledge strategy to a proven peer-led asthma education program appears to be a promising approach to motivate adolescents to abstain from smoking in Jordan. Future research is required to determine if these results can be extended to Jordanian adolescent females.

Implications

A commitment by students via a "class smoke-free" pledge can be an added incentive to motivate adolescents in Arabic-speaking countries to abstain from smoking. Social influence approaches in schools can be useful in countering the aggressive tobacco marketing campaigns targeting Jordanian and other Arabic-speaking youth. The combination of "class smoke-free" pledges and an evidence-based peer-led asthma and smoking education can be implemented in schools to influence adolescents with asthma to abstain from smoking.

[School-based tobacco prevention: the "Be Smart - Don't Start" program]

The competition for smoke-free classes, the "Be Smart - Don't Start" program has been implemented in Germany since 1997. Using contract management techniques, school classes participating in the competition commit themselves to abstain from smoking for six months. Classes report on a regular basis whether they have stayed smoke-free or not. After the end of the competition period, successful classes participate in a prize draw. The competition aimes to influence social norms.Over the past 20 years, the competition has become a major school-based intervention to prevent smoking in Germany. Several studies addressed process and outcome evaluation, cost-benefit efficacy and iatrogenic effects. Following the evidence so far, the intervention is feasible for implementation in school routines, evokes positive feedback in teachers and students, and reveals a positive cost-benefit ratio. Findings from controlled studies imply that negative side-effects are unlikely to occur and that participation in the competition affects the progression of smoking positively at least in the short term.

Behavioural incentive interventions for health behaviour change in young people (5-18 years old): A systematic review and meta-analysis

Physical inactivity, an unhealthy diet, smoking, and alcohol consumption are key determinants of morbidity and mortality. These health behaviours often begin at a young age and track into adulthood, emphasising a need for interventions in children and young people. Previous research has demonstrated the potential effectiveness of behavioural incentive (BI) interventions in adults. However, little is known about their effectiveness in children and adolescents. Eight bibliographic databases were searched. Eligibility criteria included controlled trials using behavioural incentives (rewards provided contingent on successful performance of the target behaviour) as an intervention component for health behaviour change in children and adolescents. Intervention effects (standardised mean differences or odds ratios) were calculated and pooled by health behaviour, using a random effects model. Twenty-two studies were included (of n = 8392 identified), 19 of which were eligible for meta-analysis: physical activity (n = 8); healthier eating (n = 3); and smoking (n = 8). There was strong evidence that behavioural incentives may encourage healthier eating behaviours, some evidence that behavioural incentives were effective for encouraging physical activity behaviour, and limited evidence to support the use of behavioural incentives for smoking cessation and prevention in adolescents. Findings suggest that behavioural incentives may encourage uptake and initiation of healthy eating and physical activity in young people. However, this is a limited evidence base and a wide range of incentive designs have yet to be explored. Future research should further investigate the acceptability of these intervention approaches for young people.

„Be Smart – Don’t Start“: Untersuchung langfristiger Effekte eines schulbasierten Präventionsprogramms

Zusammenfassung. Zielsetzung: Zur Beeinflussung der sozialen Norm verpflichten sich beim schulischen Nichtraucherwettbewerb „Be Smart – Don’t Start“ Schulklassen für 6 Monate nicht zu rauchen. Ziel der Studie war, die langfristige Wirksamkeit des Wettbewerbs zu untersuchen. Methodik: 2006 nahmen 3.490 Schüler der 7. Klassenstufe aus 84 Schulen des Landes Sachsen-Anhalt an einer cluster-randomisierten Begleitstudie teil. Diese Stichprobe wurde 2015, neun Jahre nach der Eingangserhebung, erneut kontaktiert und zu ihrem Rauchverhalten befragt. Endpunkte der Untersuchung waren Nierauchen, tägliches Rauchen, Rauchbeginn und Rauchstopp. Ergebnisse: 58 Schulen (69,0 %) erklärten sich zur Teilnahme an der Folgeuntersuchung bereit. Daraus resultierten 688 (19,7 %) Fragebogen von ehemaligen Schülern, die der Eingangserhebung zugeordnet werden konnten (mittleres Alter in 2015: 21,2 Jahre). Personen mit niedrigerem Risiko für das Rauchen wurden bei der Nachuntersuchung häufiger erreicht. Es zeigte sich darüber hinaus, dass in der Kontrollgruppe überzufällig häufig Gymnasiasten erreicht wurden. Nahezu alle Analysen wiesen auf numerisch günstigere Werte in der Interventions- im Vergleich zur Kontrollgruppe hin; dieser Unterschied wurde für den Rauchstopp auch statistisch bedeutsam. Schlussfolgerungen: Aufgrund der geringen Stichprobengröße sowie der differentiellen Attrition sind Schlussfolgerungen zu langfristigen Effekten einer Wettbewerbsteilnahme nur mit großer Vorsicht zu ziehen.

Incentives for preventing smoking in children and adolescents

BACKGROUND

Adult smoking usually has its roots in adolescence. If individuals do not take up smoking during this period it is unlikely that they ever will. Further, once smoking becomes established, cessation is challenging; the probability of subsequently quitting is inversely proportional to the age of initiation. One novel approach to reducing the prevalence of youth smoking is the use of incentives.

OBJECTIVES

To assess the effect of incentives on preventing children and adolescents (aged 5 to 18 years) from starting to smoke. It was also our intention to assess, where possible, the dose-response of incentives, the costs of incentive programmes, whether incentives are more or less effective in combination with other interventions to prevent smoking initiation, and any unintended consequences arising from the use of incentives.

SEARCH METHODS

For the original review (published 2012) we searched the Cochrane Tobacco Addiction Group Specialized Register, with additional searches of MEDLINE, Embase, CINAHL, CSA databases and PsycINFO for terms relating to incentives, in combination with terms for smoking and tobacco use, and children and adolescents. The most recent searches were of the Cochrane Tobacco Addiction Group Specialized Register, and were carried out in December 2016.

SELECTION CRITERIA

We considered randomized controlled trials (RCTs) allocating children and adolescents (aged 5 to 18 years) as individuals, groups or communities to intervention or control conditions, where the intervention included an incentive aimed at preventing smoking uptake. We also considered controlled trials (CTs) with baseline measures and post-intervention outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors extracted and independently assessed the data. The primary outcome was the smoking status of children or adolescents at follow-up who reported no smoking at baseline. We required a minimum follow-up of six months from baseline and assessed each included study for risks of bias. We used the most rigorous definition of abstinence in each trial; we did not require biochemical validation of self-reported tobacco use for study inclusion. Where possible we combined eligible studies to calculate pooled estimates at the longest follow-up, using the Mantel-Haenszel fixed-effect method, grouping studies by study design.

MAIN RESULTS

We identified three eligible RCTs and five CTs, including participants aged 11 to 14 years, who were non-smokers at baseline. Of the eight trials identified, six had analyzable data relevant for this review, which contributed to meta-analyses (7275 participants in total: 4003 intervention; 3272 control; 2484 participants after adjusting for clustering). All except one of the studies tested the 'Smokefree Class Competition' (SFC), which has been widely implemented throughout Europe. In this competition, classes with youth generally between the ages of 11 and 14 years commit to being smoke-free for a six-month period, and report their smoking status regularly. If 90% or more of the class are non-smokers at the end of the six months, the class goes into a competition to win prizes. The one study that was not a trial of the SFC was a controlled trial in which schools in two communities were assigned to the intervention, with schools in a third community acting as controls. Students in the intervention community with lower smoking rates at the end of the project (one school year) received rewards.Most studies resulted in statistically non-significant results. Only one study of the SFC reported a significant effect of the competition on the prevention of smoking at the longest follow-up. However, this study was at risk of multiple biases, and when we calculated the adjusted risk ratio (RR) we no longer detected a statistically significant difference. The pooled RR for the more robust RCTs (3 studies, n = 3056 participants/1107 adjusted for clustering) suggests that there is no statistically significant effect of incentives, in the form of the SFC, to prevent smoking initiation among children and adolescents in the long term (RR 1.00, 95% confidence interval (CI) 0.84 to 1.19). Pooled results from the non-randomized trials also did not detect a significant effect of the SFC, and we were unable to extract data on our outcome of interest from the one trial that did not study the SFC. There is little robust evidence to suggest that unintended consequences (such as making false claims about their smoking status and bullying of smoking students) are consistently associated with such interventions, although this has not been the focus of much research. There was insufficient information to assess the dose-response relationship or to report costs of incentives for preventing smoking uptake.We judged the included RCTs to be at unclear risk of bias, and the non-RCTs to be at high risk of bias. Using GRADE, we rated the overall quality of the evidence for our primary outcome as 'low' (for RCTs) and 'very low' (for non-RCTs), because of imprecision (all studies had wide confidence intervals), and for the risks of bias identified. We further downgraded the non-RCT evidence, due to issues with the non-RCT study design, likely to introduce further bias.

AUTHORS' CONCLUSIONS

The very limited evidence currently available suggests that incentive programmes do not prevent smoking initiation among youth. However, there are relatively few published studies and these are of variable quality. In addition, trials included in the meta-analyses were all studies of the SFC, which distributed small to moderately-sized prizes to whole classes, usually through a lottery system. It is therefore possible that other incentive programmes could be more successful at preventing smoking uptake in young people.Future studies might investigate the efficacy of a wider range of incentives, including those given to individual participants to prevent smoking uptake, whilst considering both the effect of incentives on smoking initiation and the progression to smoking. It would be useful if incentives were evaluated in varying populations from different socioeconomic and ethnic backgrounds, and if intervention components were described in detail.

Long-term effectiveness of a combined student-parent and a student-only smoking prevention intervention among 7th grade school children in Berlin, Germany

BACKGROUND AND AIMS

In Germany, the smoking prevalence among adolescents is among the highest in Europe. Our aim was to evaluate the long-term effectiveness of a combined student-parent and a student-only smoking prevention programme to reduce the smoking prevalence among 7th grade students in Berlin.

DESIGN

Three-armed cluster-randomized controlled trial (RCT). Schools as cluster units were randomized into (i) student intervention, (ii) combined student-parent intervention or (iii) control group, with follow-up after 12 and 24 months.

SETTING

High schools and integrated secondary schools in Berlin, Germany.

PARTICIPANTS

Seventh grade students aged 11-16 years. We included 47 schools, 161 classes and 2801 students [50.1% girls, mean age ± standard deviation (SD) = 13.0 ± 0.6 years].

MEASUREMENTS

The primary outcome was self-reported regular smoking (at least one cigarette per day) after 24 months (point prevalence). Further self-reported outcomes were other smoking behaviours as well as parental rules and attitudes towards smoking. Comparisons were calculated as odds ratios (OR) with 95% confidence intervals (CI).

FINDINGS

At baseline, 2.3% of the students reported that they smoked regularly. After 24 months, 7.8% and 7.0% were regular smokers in the student-only intervention and the student-parent intervention, respectively, compared with 10.1% in the control group. The OR for being a regular smoker was 0.81 (0.34-1.92) for the student-parent intervention versus control, 0.95 (CI = 0.41-2.22) for the student-only intervention versus control and 0.85 (0.38-1.89) for student-parent intervention versus student-only intervention.

CONCLUSION

A combined student-parent smoking prevention intervention delivered via secondary schools in Berlin, Germany did not result in a statistically significant reduction in regular smoking compared with a control group or a student-only intervention. The student-only intervention did not result in a significant reduction in regular smoking compared with the control group.

Evaluating the effectiveness of the SMART contract-signing strategy in reducing the growth of Swedish Adolescents' substance use and problem behaviors

BACKGROUND

In 2013, around 40 % of the schools in Sweden had structured programs to prevent tobacco and alcohol debut in compulsory school. There has unfortunately been a lack of scientific evidence to support most of the prevention methods focusing on primary prevention in schools in Sweden. The aim and purpose of the present study is to evaluate the effectiveness of the Non-Governmental Organization SMART contract-signing strategy in reducing the growth of youth substance use and other problem behaviors amongst Swedish adolescents.

METHODS

Students from five schools in a medium-sized Swedish municipality were surveyed in three waves from 7(th) to 9(th) grade of compulsory school. We used General Linear Model (GLM) repeated-measures ANOVA to test if the outcome measures smoking, use of snus and alcohol, drunkenness, delinquency, and bullying significantly changed different amounts over time in groups that had participated in the SMART program for long time, a short time, sporadically- or not at all. Groups were compared on demographic background variables, and outcome measures were assessed on all measurement occasions by a one-way ANOVA. The magnitude of group differences at the end of the study was estimated according to Cohen's d.

RESULTS

Number of years with a contract has an effect on the levels of self-reported youth problems in 9(th) grade. We found small to medium-sized differences in measured outcomes between students who participated in the program for the longest period of time, 5 years, and who participated for the shortest time, 0-2 years.

CONCLUSION

Findings suggests that the SMART program has preventive effects on adolescent substance use.

'Klar bleiben': a school-based alcohol prevention programme for German adolescents-study protocol for a cluster randomised controlled trial

INTRODUCTION

There is a noticeable increase in hazardous alcohol use during adolescence, which is significantly associated with adverse consequences. In Germany, up to 30% of adolescents report regular heavy episodic drinking. However, only a few German prevention programmes target adolescents of legal drinking age (16 years and above); thus, this trial aims to develop, implement and evaluate 'Klar bleiben' ('Stay clearheaded'), a school-based prevention programme for grade 10 students.

METHODS AND ANALYSIS

'Klar bleiben' consists of a class commitment to drink responsibly and refrain from hazardous consumption patterns for 9 weeks. The commitment is accompanied by educational lessons on alcohol-related cognitions and consequences. It will be evaluated in a sample of approximately 3000 students (150 classes) from two German federal states (Schleswig-Holstein and Lower Saxony) via a two-armed cluster randomised controlled trial with baseline and postassessment 6 months apart. The intervention group (75 classes) will participate in 'Klar bleiben', whereas the control group (75 classes) will receive education as usual. 'Klar bleiben' addresses classes, individuals, teachers and parents. It is based on a social norms approach and aims to reduce hazardous drinking and drinking-related consequences in adolescents. Secondary outcomes include general drinking behaviour, use of other substances, alcohol-related cognitions and social factors. Covariates include sociodemographic characteristics, environmental and individual (vulnerability) factors.

ETHICS AND DISSEMINATION

'Klar bleiben' provides a multicomponent school-based programme that bridges a gap in alcohol prevention. Similar class-level and social norms-based prevention programmes have already been proven to be successful for other substances among adolescents. Thus, dissemination to other federal states as well as longer term follow-up testing of the robustness of effects is to be anticipated. The study was approved by the Ethics Committee of the German Psychological Society (RH_0620152), and study findings will be disseminated through peer-reviewed publications and conference contributions.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register: DRKS00009424.

The Effects of Antismoking Messages From Family, School, and Mass Media on Smoking Behavior and Smoking Intention Among Chinese Adolescents

The prevalence of adolescent smoking has been increasing rapidly in China. Expanding adolescent exposure to antismoking messages may be an effective approach to prevent tobacco use among this population. Using a cross-sectional sample of 8,444 high school students in four Chinese cities, this study assessed the relation between self-reported exposure to antismoking messages from families, schools, and mass media and the rate of past 30-day smoking and smoking intention among junior and senior high school students. Results from logistic regression suggested that antismoking messages delivered via school and media inhibited both tobacco use and the intention to smoke. The effects of familial warnings about harmful effects of smoking, in contrast, were at best insignificant.

Does smoking within an individual's peer group affect intervention effectiveness? An evaluation of the Smoke-Free Class Competition among Swiss adolescents

OBJECTIVE

The aim of this study is to test whether participation in the Smoke-Free Class Competition (SFC), a classroom-based smoking prevention program, reduced smoking and increased smoking-related knowledge among those with and without smoking peers compared to control groups.

METHOD

Including smoking peers as a moderator in multilevel models, a quasi-experimental design with a post-test at seven months was used to analyze data from 1035 students in Switzerland (2011; mean age 13.3, 53.2% female).

RESULTS

Completing the SFC decreased smoking prevalence (OR=0.7; CI=0.5-1.0; ns) and increased smoking-related knowledge (b=1.0; p<.01) compared to control classes. However, the former effect was only significant among those without smoking peers (OR=0.3; CI=0.2-0.5; p<.001). With smoking peers, smoking prevalence was even higher at post-test (OR=3.7; CI=1.7-8.2; p<.01) in the classes that completed SFC compared to controls. No effect was found in classes that started SFC but had to pull out.

CONCLUSIONS

The results indicate that SFC should be applied early in adolescence, when individuals are less likely to have classmates who smoke and are therefore less likely to have to pull out of the program. This is particularly important because SFC was only effective among those who completed the program and did not have smoking peers.

School-based programmes for preventing smoking

BACKGROUND

Helping young people to avoid starting smoking is a widely endorsed public health goal, and schools provide a route to communicate with nearly all young people. School-based interventions have been delivered for close to 40 years.

OBJECTIVES

The primary aim of this review was to determine whether school smoking interventions prevent youth from starting smoking. Our secondary objective was to determine which interventions were most effective. This included evaluating the effects of theoretical approaches; additional booster sessions; programme deliverers; gender effects; and multifocal interventions versus those focused solely on smoking.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Tobacco Addiction Group's Specialised Register, MEDLINE, EMBASE, PsycINFO, ERIC, CINAHL, Health Star, and Dissertation Abstracts for terms relating to school-based smoking cessation programmes. In addition, we screened the bibliographies of articles and ran individual MEDLINE searches for 133 authors who had undertaken randomised controlled trials in this area. The most recent searches were conducted in October 2012.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) where students, classes, schools, or school districts were randomised to intervention arm(s) versus a control group, and followed for at least six months. Participants had to be youth (aged 5 to 18). Interventions could be any curricula used in a school setting to deter tobacco use, and outcome measures could be never smoking, frequency of smoking, number of cigarettes smoked, or smoking indices.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed studies for inclusion, extracted data and assessed risk of bias. Based on the type of outcome, we placed studies into three groups for analysis: Pure Prevention cohorts (Group 1), Change in Smoking Behaviour over time (Group 2) and Point Prevalence of Smoking (Group 3).

MAIN RESULTS

One hundred and thirty-four studies involving 428,293 participants met the inclusion criteria. Some studies provided data for more than one group.Pure Prevention cohorts (Group 1) included 49 studies (N = 142,447). Pooled results at follow-up at one year or less found no overall effect of intervention curricula versus control (odds ratio (OR) 0.94, 95% confidence interval (CI) 0.85 to 1.05). In a subgroup analysis, the combined social competence and social influences curricula (six RCTs) showed a statistically significant effect in preventing the onset of smoking (OR 0.49, 95% CI 0.28 to 0.87; seven arms); whereas significant effects were not detected in programmes involving information only (OR 0.12, 95% CI 0.00 to 14.87; one study), social influences only (OR 1.00, 95% CI 0.88 to 1.13; 25 studies), or multimodal interventions (OR 0.89, 95% CI 0.73 to 1.08; five studies). In contrast, pooled results at longest follow-up showed an overall significant effect favouring the intervention (OR 0.88, 95% CI 0.82 to 0.96). Subgroup analyses detected significant effects in programmes with social competence curricula (OR 0.52, 95% CI 0.30 to 0.88), and the combined social competence and social influences curricula (OR 0.50, 95% CI 0.28 to 0.87), but not in those programmes with information only, social influence only, and multimodal programmes.Change in Smoking Behaviour over time (Group 2) included 15 studies (N = 45,555). At one year or less there was a small but statistically significant effect favouring controls (standardised mean difference (SMD) 0.04, 95% CI 0.02 to 0.06). For follow-up longer than one year there was a statistically nonsignificant effect (SMD 0.02, 95% CI -0.00 to 0.02).Twenty-five studies reported data on the Point Prevalence of Smoking (Group 3), though heterogeneity in this group was too high for data to be pooled.We were unable to analyse data for 49 studies (N = 152,544).Subgroup analyses (Pure Prevention cohorts only) demonstrated that at longest follow-up for all curricula combined, there was a significant effect favouring adult presenters (OR 0.88, 95% CI 0.81 to 0.96). There were no differences between tobacco-only and multifocal interventions. For curricula with booster sessions there was a significant effect only for combined social competence and social influences interventions with follow-up of one year or less (OR 0.50, 95% CI 0.26 to 0.96) and at longest follow-up (OR 0.51, 95% CI 0.27 to 0.96). Limited data on gender differences suggested no overall effect, although one study found an effect of multimodal intervention at one year for male students. Sensitivity analyses for Pure Prevention cohorts and Change in Smoking Behaviour over time outcomes suggested that neither selection nor attrition bias affected the results.

AUTHORS' CONCLUSIONS

Pure Prevention cohorts showed a significant effect at longest follow-up, with an average 12% reduction in starting smoking compared to the control groups. However, no overall effect was detected at one year or less. The combined social competence and social influences interventions showed a significant effect at one year and at longest follow-up. Studies that deployed a social influences programme showed no overall effect at any time point; multimodal interventions and those with an information-only approach were similarly ineffective.Studies reporting Change in Smoking Behaviour over time did not show an overall effect, but at an intervention level there were positive findings for social competence and combined social competence and social influences interventions.

Incentives for preventing smoking in children and adolescents

BACKGROUND

Adult smoking usually has its roots in adolescence. If individuals do not take up smoking during this period it is unlikely that they ever will. Further, once smoking becomes established, cessation is challenging; the probability of subsequently quitting is inversely proportional to the age of initiation. One novel approach to reducing the prevalence of youth smoking is the use of incentives.

OBJECTIVES

To determine whether incentives prevent children and adolescents from starting to smoke. We also attempted to assess the dose-response of incentives, the costs of incentive programmes, whether incentives are more or less effective in combination with other interventions to prevent smoking initiation and any unintended consequences arising from the use of incentives.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialized Register, with additional searches of MEDLINE, EMBASE, CINAHL, CSA databases and PsycINFO for terms relating to incentives, in combination with terms for smoking and tobacco use, and children and adolescents. The most recent searches were in May 2012.

SELECTION CRITERIA

We considered randomized controlled trials allocating children and adolescents (aged 5 to 18 years) as individuals, groups or communities to intervention or control conditions, where the intervention included an incentive aimed at preventing smoking uptake. We also considered controlled trials with baseline measures and post-intervention outcomes.

DATA COLLECTION AND ANALYSIS

Data were extracted by two authors and assessed independently. The primary outcome was the smoking status of children or adolescents at follow-up who reported no smoking at baseline. We required a minimum follow-up of six months from baseline and assessed each included study for risk of bias. We used the most rigorous definition of abstinence in each trial; we did not require biochemical validation of self-reported tobacco use for study inclusion. Where possible we combined eligible studies to calculate pooled estimates at the longest follow-up using the Mantel-Haenszel fixed-effect method, grouping studies by study design.

MAIN RESULTS

We identified seven controlled studies that met our inclusion criteria, including participants with an age range of 11 to 14 years. Of the seven trials identified, only five had analysable data relevant for this review and contributed to the meta-analysis (6362 participants in total who were non-smokers at baseline; 3466 in intervention and 2896 in control). All bar one of the studies was a trial of the so-called Smokefree Class Competition (SFC), which has been widely implemented throughout Europe. In this competition, classes with youth generally between the ages of 11 to 14 years commit to being smoke free for a six month period. They report regularly on their smoking status; if 90% or more of the class is non-smoking at the end of the six months, the class goes into a competition to win prizes. The one study that was not a trial of the SFC was a controlled trial in which schools in two communities were assigned to the intervention, with schools in a third community acting as controls. Students in the intervention community with lower smoking rates at the end of the project (one school year) received rewards.Only one study of the SFC competition, a non-randomized controlled trial, reported a significant effect of the competition on the prevention of smoking at the longest follow-up. However, this study had a risk of multiple biases, and when we calculated the adjusted RR we no longer detected a statistically significant difference. The pooled RR for the more robust RCTs (3 studies, n = 3056 participants) suggests that, from the available data, there is no statistically significant effect of incentives to prevent smoking initiation among children and adolescents in the long term (RR 1.00, 95% CI 0.84 to 1.19). Pooled results from non-randomized trials also did not detect a significant effect, and we were unable to extract data on our outcome of interest for the one trial that did not study the SFC. There is little robust evidence to suggest that unintended consequences (such as youth making false claims about their smoking status and bullying of smoking students) are consistently associated with such interventions, although this has not been the focus of much research. There was insufficient information to assess the dose-response relationship or to report costs.

AUTHORS' CONCLUSIONS

To date, incentive programmes have not been shown to prevent smoking initiation among youth, although there are relatively few published studies and these are of variable quality. Trials included in this meta-analysis were all studies of the SFC competition, which distributed small to moderately sized prizes to whole classes, usually through a lottery system.Future studies might investigate the efficacy of incentives given to individual participants to prevent smoking uptake. Future research should consider the efficacy of incentives on smoking initiation, as well as progression of smoking, evaluate these in varying populations from different socioeconomic and ethnic backgrounds, and describe the intervention components in detail.

[Process evaluation in relation to effectiveness assessment: experiences with school-based programs]

Evaluation of public health interventions usually focus on the quality of design and research methods, and less on the quality of the intervention or process evaluation. In process evaluation of school-based interventions, key issues are how completely the intervention is carried out and adherence to the protocol. In addition, exploration of intermediate variables, such as those that influence (and often predict) preventable behavior, is highly useful. This article describes the basic concepts in this topic, using examples of the effectiveness of some preventive interventions carried out in schools. The interventions discussed were mainly quasi-experimental studies, based on data from programs promoted by public health teams in the city of Barcelona. Data from process evaluation of preventive programs in secondary schools that underwent formal assessment of their effectiveness is provided. The examples are drawn from preventive programs of HIV infection or unprotected sexual intercourse (PRESSEC program) and drug consumption prevention (the PASE, PASE.bcn and x kpts programs). These examples show why the intervention process influences the impact of the programs and their results. Thorough planning of process evaluation is essential to obtain valid indicators that will identify, in the effectiveness evaluation of the intervention, the most efficacious strategies to obtain positive outcomes.

Meta-analysis on the effects of the smoke-free class competition on smoking prevention in adolescents

BACKGROUND

The 'Smoke-Free Class competition' (SFC) is a school-based smoking prevention programme including commitment not to smoke, contract management and prizes as rewards broadly implemented in Europe.

OBJECTIVES

To meta-analyse (randomised) controlled trials on the effects of SFC on current smoking at latest follow-up in adolescents.

METHODS

A systematic review of articles using MEDLINE and the Cochrane Library was conducted. The study selection included randomised controlled trials and controlled trials with follow-up assessment that investigated the efficacy of SFC on current smoking in students participating in SFC compared to non-participating students. Independent extraction of articles was performed by both authors.

RESULTS

Of 24 records identified, five fulfilled the inclusion criteria. These studies were conducted in three European countries (Finland, The Netherlands and Germany) and recruited 16,302 students altogether. A random effects meta-analysis of these five studies revealed a pooled risk ratio of 0.86 (95% CI 0.79-0.94; z = 3.44, p = 0.001) on current smoking at follow-up by participation in the competition.

CONCLUSION

SFC appears to be an effective tool in school-based smoking prevention.

Smoking initiation in Germany: the role of intergenerational transmission

This paper analyzes the decision to start smoking using data from the German Socio-Economic Panel (GSOEP). Our focus is on the role that parental smoking behavior plays for children's smoking initiation. The data used are a combination of retrospective information on the age individuals started smoking and, by tracing back these individuals within the panel structure up to that point, information on characteristics at the age of smoking initiation. In contrast to the previous literature it is possible to control for the environment at the time of smoking onset that might have influenced the decision to start. Our preferred specification of a discrete time hazard model indicates that parental smoking significantly increases the offspring's hazard to start smoking. While this effect is most prominent for currently smoking parents, it is also found for parents who have given up smoking already. However, an ambiguous effect of the timing of parental smoking cessation is found, arguing against role-model effects being a key determinant for smoking initiation.

The promise of long-term effectiveness of school-based smoking prevention programs: a critical review of reviews

I provide a review and critique of meta-analyses and systematic reviews of school-based smoking prevention programs that focus on long-term effects. Several of these reviews conclude that the effects of school-based smoking prevention programs are small and find no evidence that they have significant long-term effects. I find that these reviews all have methodological problems limiting their conclusions. These include severe limiting of the studies included because of performance bias, student attrition, non-reporting of ICCs, inappropriate classification of intervention approach, and inclusion of programs that had no short-term effects. The more-inclusive meta-analyses suggest that school-based smoking prevention programs can have significant and practical effects in both the short- and the long-term. Findings suggest that school-based smoking prevention programs can have significant long-term effects if they: 1) are interactive social influences or social skills programs; that 2) involve 15 or more sessions, including some up to at least ninth grade; that 3) produce substantial short-term effects. The effects do decay over time if the interventions are stopped or withdrawn, but this is true of any kind of intervention.

I do not smoke -- I exercise: a pilot study of a new educational resource for secondary education students

AIMS

The aim of this study was to examine the applicability of a smoking prevention educational resource for secondary education students named ;I do not smoke, I exercise'. The main focus of this program was the promotion of exercise as an alternative behaviour to smoking.

METHODS

The applicability of the intervention was assessed through questionnaires regarding: (a) attitudes towards smoking, (b) interest in information about smoking, and (c) knowledge about health consequences of smoking. Moreover, interviews were taken from the educators and the school principals. The questionnaires were completed from 210 students (101 boys and 109 girls) before the beginning, at the end of the program, and 12 months after the completion of the programme. One-way repeated measure ANOVA was performed to examine the differences between the pre-, post-, and the follow-up measures.

RESULTS

Results showed that the program succeeded in changing the students' attitudes, but the follow-up measures, 12 months later, showed that attitudes towards smoking and interest in information were relapsed to the pre-intervention levels. The only effect that was sustained was that for knowledge. The interviews also revealed positive comments about the program implementation and pointed some shortcomings.

CONCLUSIONS

The program needs some modifications in order to overcome its weaknesses, have more lasting effects and to improve its applicability.

Risk factors for smoking among school adolescents in Greece

OBJECTIVE

We conducted this study among school adolescents to identify factors, which influence schoolchildren to smoke.

METHODS

We carried out a cross-sectional study in a sample of 924 students of all classes (ages 12-18 years old) in 15 public high schools in a semi-urban area in Crete, Greece, using a questionnaire. The questionnaire comprised of 46 questions covering children's lifestyle habits regarding daily activities and leisure time, frequency of risk-taking behaviour, knowledge about the hazards and long-term consequences of smoking.

RESULTS

23.9% of participants were experimental smokers and 18.6% were current smokers. 11.4% of the total population was daily smokers. There was a significant increase in the prevalence of experimental and current smokers with school grades, while peaks in last grades were observed. Boys started smoking earlier than girls, mean (standard error) age 13.4 (2.3) years vs. 14.1 (2.3) years, P = 0.01. Stepwise logistic regression analysis showed a positive relationship between current smoking and having brother or sister smoking [odds ratio (95% confidence interval) 2.7 (1.7-4.4) and 1.8 (1.1-3.3) respectively], having more than three friends who were smokers [2.6 (2-3.4)] and last school grade [1.4 (1.2-1.7)]. Students appeared to be informed about long-term smoking hazards and had negative views on children who smoke especially in the lower grades.

CONCLUSIONS

Prevention programmes should be imposed early in elementary schools while cessation policies should target at all grades, in particular at critical grades depending on population-specific characteristics.

Do school-based tobacco prevention programmes pay off? The cost-effectiveness of the 'Smoke-free Class Competition'

OBJECTIVE

The objective of this study was to determine the cost-effectiveness of a school-based tobacco prevention programme.

STUDY DESIGN

Using data from a previous effectiveness study of the 'Smoke-free Class Competition' (SFC), an economic analysis was conducted to determine the cost-effectiveness of the SFC. Cost data were collected from financial statements of the operating agency, surveys of regional co-ordinators and participating classes (direct and productivity costs). The benefit was the product of the number of students prevented from becoming established smokers, based on a stochastic progression model extending the programme's outcome evaluation, and the (direct and indirect) value per prevented smoker.

INTERVENTION

To take part in the SFC, classes make the decision to be a non-smoking class for 6 months (from autumn to spring). The pupils themselves and their teachers monitor the smoking status of the pupils and report on it regularly. Classes that refrain from smoking can win a number of attractive prizes. In the school year 2001/2002, 150,566 German students participated in the SFC, representing approximately 4% of the total target population of 11-14-year-old German students. The effectiveness evaluation is based on 2,142 students who participated in the programme in the school year 1998/1999.

RESULTS

In the school year 2001/2002, it is estimated that the SFC prevented 3,076 students from becoming established smokers, with net benefits of 5.59 Mio. Euro (direct net benefits) and 15.00 Mio. Euro (total net benefits). The direct benefit/cost ratio was 8.2 and the total benefit/cost ratio was 3.6.

CONCLUSIONS

Data suggest that the SFC is a cost-effective school-based intervention.

Some doubts about one of the largest smoking prevention programmes in Europe, the smokefree class competition

With over 600,000 participants in 16 countries, the smokefree class competition is one of the largest smoking prevention programmes in Europe. Participating classes that maintain a smoking prevalence usually below 10% are eligible for a contest and the winner is rewarded with money. There is however no convincing evidence that this competition has any effect on smoking prevalence beyond the short term, and this approach raises serious ethical issues. In particular, the central principle of this competition is to apply negative peer pressure upon teenage smokers. However, promoters of this competition have neglected to report the possible adverse consequences of using negative peer pressure upon smokers. This is a concern, because teenage smokers are more vulnerable than non-smokers, and they are at higher risk of suffering from psychological problems and school failure.

Survey of smoking attitudes in grade school children in Greece: a preliminary study

AIMS

Tobacco use among children and adolescents is a major public health concern. Past literature has indicated that smoking attitudes are reliable predictors of teen smoking. The present study explored the smoking attitudes of 4th-6th grade Greek pupils.

METHODS

Data were obtained from 379 Greek elementary school students who completed a smoking attitudes survey, based on the Bogalusa Heart Study.

FINDINGS AND CONCLUSIONS

Analysis of variance indicated that 4th graders expressed significantly more positive attitudes towards tobacco use in three statements related to the psychological consequences of cigarette use, and to peer pressures to smoke. No gender differences were evident. Overall, pupils across grades expressed relatively negative attitudes towards smoking. Differences between school grades in certain statements denoting the psychological properties of tobacco use, and in peer pressures were attributed to 4th graders' lack of knowledge in the particular areas.

Lack of sustainable prevention effect of the "Smoke-Free Class Competition" on German pupils

BACKGROUND

This study examines the effectiveness of the school-based campaign "Smoke-Free Class Competition" as a means of preventing young non-smokers from taking up smoking.

METHODS

Based on two measurements of the Heidelberg Children's Panel Study (1998 and 2000), a longitudinal sample of 1704 pupils was examined: 948 in the intervention group and 756 in the control group. In order to evaluate the effects of the intervention, we compared the smoking behavior in the intervention and the control group at two points in time, shortly before, and 18 months after the intervention, on an individual case basis.

RESULTS

(1) Stabilization of never-smoking rates: the proportion of pupils remaining a never-smoker at the follow-up is 62.1% in the intervention group and 61.5% in the control group (OR 1.02, 95% CI: 0.83-1.24); (2) Lowering of relapse rates among ex-smokers: the proportion of former smokers who had not started smoking again in the follow-up is 45.1% in the intervention group and 41.4% in the control group (OR 1.07, 95% CI: 0.77-1.49).

CONCLUSION

The "Smoke-Free Class Competition" did not prevent smoking among adolescents and does not appear to be an effective substitute to the complete ban of tobacco advertising, the abolition of vending machines and the creation of smoke-free environments in German schools.