The 'Eigenstandig werden' prevention trial: a cluster randomised controlled study on a school-based life skills programme to prevent substance use onset

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.

Moderation, mediation - or even both? School climate and the association between peer and adolescent alcohol use

INTRODUCTION

Ample studies discuss the enhancing effects of peer drinking on student alcohol use. In addition, there is vast research on school climate impact on student alcohol use. Though these two areas are intertwined for most young adolescents, it is heretofore not completely clear, in what way these characteristics functionally interact and affect drinking behavior.

METHODS

In a longitudinal study, we analyzed a sample of 2490 German adolescents (Mage=13.32, SD=0.57, range=8-13) from 5th (fall 2010) to 8th (fall 2013) grade. We discerned mediating (class climate) and moderating (school organization variables) functions of school on the association between peer and adolescent alcohol use, and finally combined them in direct effect moderated mediation models for a variety of outcomes (lifetime alcohol use, frequency and amount of drinking, binge drinking), adjusting for possible confounders.

RESULTS

Class climate mediated a small significant part of the association between peer and adolescent alcohol use (1.8-2.4%), with the exception of lifetime drinking. Student-teacher ratio and percentage of at-risk students significantly moderated the peer-adolescent association, with the latter having an enhancing and the first having a buffering effect.

CONCLUSIONS

School life serves as an important context of adolescent development and as such, seems to have direct and indirect effects on behavior and health. Future research should pay attention to differentiating effects of school climate and include both forms of operationalization when analyzing school effects on student behavior.

'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.

Multiple substance use patterns in adolescents-A multilevel latent class analysis

BACKGROUND

Multiple substance use among adolescents is associated with a number of negative consequences. Therefore, we aim to investigate multiple substance use patterns among young adolescents and identify possible multilevel predictors.

METHODS

We analyzed a longitudinal sample of 2490 German students (51% male; Mage=13.32, SD=0.57) at 45 schools in four German states (Bremen, Hesse, North Rhine-Westphalia, Schleswig-Holstein), who completed two assessments in fall, 2010 and fall, 2013. We conducted multilevel latent class analysis for follow-up data on a variety of outcomes, and tested our final 3-class-model for possible baseline predictors. Follow-up substance use measures included lifetime use, current use, and amount of substance for cigarettes and alcohol. Baseline covariates comprised age, gender, socio-economic status, bullying, victimization, peer and parental use, type of school, and health certification of school.

RESULTS

We identified three latent classes: non-users (n=1541; 61.9%), experimenters (n=722; 29.0%), and multiusers (n=227; 9.1%). Experimental consumption was predicted by higher baseline age (OR=1.71; 1.31-2.24), paternal drinking (OR=2.89; 1.23-6.79), and school type (OR=2.57; 1.83-3.61), while multiuse was predicted by peer smoking (OR=2.94; 1.80-4.80) and drinking (OR=2.13; 1.32-3.44), maternal drinking (OR=6.26; 2.02-19.43), bullying (OR=1.69; 1.15-2.48), higher age (OR=1.92; 1.40-2.62), and school type (OR=4.76; 2.75-8.24) compared to the non-users class.

CONCLUSIONS

Prevention and further research on multiple substance use need to concentrate on social influence models and behavior-related interventions, especially at schools without a college-preparatory track.

Non-medical use of prescription pain relievers among high school students in China: a multilevel analysis

OBJECTIVES

Given the differences between general high school (GHS) and vocational high school (VHS) students, this study aimed to investigate the lifetime prevalence of non-medical use of prescription pain relievers (NMUPPR) among high school students as well as the associations between NMUPPR and individual-level factors and school category.

METHODS

A cross-sectional study was conducted in GHS and VHS students in 2012 in Chongqing, and 11 906 students' questionnaires were completed and qualified for the survey. Self-reported NMUPPR and information regarding individual-level determinants and school category were collected. A multilevel multivariate logistic regression model was fitted to explore independent predictors of NMUPPR.

RESULTS

The total lifetime prevalence of NMUPPR was 11.3%, and NMUPPR was more prevalent among VHS students (15.8%) compared with GHS students (9.8%). Overall, the results indicated that VHS students were more likely to be involved in NMUPPR (adjusted OR (AOR)=1.64, 95% CI 1.42 to 1.89). Regarding the individual-level predictors of NMUPPR, below-average family economic status was negatively correlated with NMUPPR (AOR=0.77, 95% CI 0.60 to 0.98), and students with more pocket money were more likely to be engaged in NMUPPR. Students who had difficult family relationships, had poor relationships with teachers, had parents or friends who engaged in non-medical prescription drug use, and considered or attempted suicide were more likely to be engaged in NMUPPR.

CONCLUSIONS

NMUPPR among high school students is a multidetermined phenomenon. The current findings indicate that VHS students are an important subgroup of adolescents and highlight the need for additional research as well as targeted prevention and intervention programmes for NMUPPR.

The Role of Substance-Specific Skills and Cognitions in the Effectiveness of a School-Based Prevention Program on Smoking Incidence

"Eigenständig werden 5+6" (Becoming independent 5+6) is a German school-based smoking prevention program that draws on social competence and social influence approaches. It was investigated whether the program's effect on smoking onset is mediated by substance-specific skills and cognitions such as knowledge, attitudes/risk perception, normative expectations, resistance skills, and refusal self-efficacy. Multiple mediation analyses revealed a statistically significant total indirect effect that accounted for 30.8% of the total effect. When considered separately, significant indirect effects could be found for normative expectations concerning peer smoking and the resistance skill of saying 'no'. Between these two mediators, the percentage of total effect mediated varied between 9.8% and 10.3%. Results of the current study emphasize the importance of substance-specific skills and cognitions in the effectiveness of school-based programs combining social competence and social influence curricula in preventing adolescent smoking onset.

Risk factors for e-cigarette, conventional cigarette, and dual use in German adolescents: a cohort study

OBJECTIVE

Little is known about risk factors that are associated with e-cigarette use in adolescents.

METHODS

Multilevel mixed-effects regressions were performed to assess the relationship between factors that might be associated with e-cigarette, conventional cigarette and dual use in a cohort of 2693 German adolescents (mean age=12.5 years; SD=0.6). Risk factors were assessed in October 2010 and life time e-cigarette and conventional cigarette use were assessed 26 months later.

RESULTS

Use of e-cigarettes as well as use of conventional cigarette and dual use were associated with higher sensation seeking scores, and higher odds of having friends and parents who smoke conventional cigarettes, with conventional cigarette use additionally with male gender, being older, having higher odds of siblings who smoke conventional cigarettes, and less likely for adolescents who attend a Gymnasium, secondary school with a strong emphasis on academic learning. The use of conventional cigarettes at baseline did not predict e-cigarette use at follow-up. Lifetime prevalence of e-cigarette use was 4.7%, of conventional cigarette use 18.4%. A quarter of e-cigarette users (23.8%) never smoked a conventional cigarette.

DISCUSSION

Data indicate that e-cigarette and conventional cigarette use share many but not all risk factors. E-cigarettes could counteract the process of denormalization of smoking.

Universal school-based prevention for illicit drug use

BACKGROUND

Drug addiction is a chronic, relapsing disease. Primary interventions should aim to reduce first use or to prevent the transition from experimental use to addiction. School is the appropriate setting for preventive interventions.

OBJECTIVES

To evaluate the effectiveness of universal school-based interventions in reducing drug use compared to usual curricular activities or no intervention.

SEARCH METHODS

We searched the Cochrane Drugs and Alcohol Group's Trials Register (September 2013), the Cochrane Central Register of Controlled Trials (2013, Issue 9), PubMed (1966 to September 2013), EMBASE (1988 to September 2013) and other databases. We also contacted researchers in the field and checked reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials (RCT) evaluating school-based interventions designed to prevent illicit drugs use.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We included 51 studies, with 127,146 participants. Programmes were mainly delivered in sixth and seventh grade pupils. Most of the trials were conducted in the USA. Social competence approach versus usual curricula or no intervention Marijuana use at < 12 months follow-up: the results favoured the social competence intervention (risk ratio (RR) 0.90; 95% confidence interval (CI) 0.81 to 1.01, four studies, 9456 participants, moderate quality evidence). Seven studies assessed this outcome (no data for meta-analysis): two showed a positive significant effect of intervention, three showed a non-significant effect, one found a significant effect in favour of the control group and one found a trend in favour of the control group.Marijuana use at 12+ months: the results favoured the social competence intervention (RR 0.86; 95% CI 0.74 to 1.00, one study, 2678 participants, high quality evidence). Seven studies assessed this outcome (no data for meta-analysis): two showed a significant positive effect of intervention, three showed a non-significant effect, one found a significant effect in favour of the control group and one a trend in favour of the control group.Hard drug use at < 12 months: we found no difference (RR 0.69; 95% CI 0.40 to 1.18, one study, 2090 participants, moderate quality evidence). Two studies assessed this outcome (no data for meta-analysis): one showed comparable results for the intervention and control group; one found a statistically non-significant trend in favour of the social competence approach.Hard drug use at 12+ months: we found no difference (mean difference (MD) -0.01; 95% CI -0.06 to 0.04), one study, 1075 participants, high quality evidence). One study with no data for meta-analysis showed comparable results for the intervention and control group.Any drug use at < 12 months: the results favoured social competence interventions (RR 0.27; 95% CI 0.14 to 0.51, two studies, 2512 participants, moderate quality evidence). One study with 1566 participants provided continuous data showing no difference (MD 0.02; 95% CI -0.05 to 0.09, moderate quality evidence). Social influence approach versus usual curricula or no intervention Marijuana use at < 12 months: we found a nearly statistically significant effect in favour of the social influence approach (RR 0.88; 95% CI 0.72 to 1.07, three studies, 10,716 participants, moderate quality evidence). One study with 764 participants provided continuous data showing results that favoured the social influence intervention (MD -0.26; 95% CI -0.48 to -0.04).Marijuana use at 12+ months: we found no difference (RR 0.95; 95% CI 0.81 to 1.13, one study, 5862 participants, moderate quality evidence). One study with 764 participants provided continuous data and showed nearly statistically significant results in favour of the social influence intervention (MD -0.22; 95% CI -0.46 to 0.02). Of the four studies not providing data for meta-analysis a statistically significant protective effect was only found by one study.Hard drug use at 12+ months: one study not providing data for meta-analysis found a significant protective effect of the social influence approach.Any drug use: no studies assessed this outcome. Combined approach versus usual curricula or no intervention Marijuana use at < 12 months: there was a trend in favour of intervention (RR 0.79; 95% CI 0.59 to 1.05, three studies, 8701 participants, moderate quality evidence). One study with 693 participants provided continuous data and showed no difference (MD -1.90; 95% CI -5.83 to 2.03).Marijuana use at 12+ months: the results favoured combined intervention (RR 0.83; 95% CI 0.69 to 0.99, six studies, 26,910 participants, moderate quality evidence). One study with 690 participants provided continuous data and showed no difference (MD -0.80; 95% CI -4.39 to 2.79). Two studies not providing data for meta-analysis did not find a significant effect.Hard drug use at < 12 months: one study with 693 participants provided both dichotomous and continuous data and showed conflicting results: no difference for dichotomous outcomes (RR 0.85; 95% CI 0.63 to 1.14), but results in favour of the combined intervention for the continuous outcome (MD -3.10; 95% CI -5.90 to -0.30). The quality of evidence was high.Hard drug use at 12+ months: we found no difference (RR 0.86; 95% CI 0.39 to 1.90, two studies, 1066 participants, high quality evidence). One study with 690 participants provided continuous data and showed no difference (MD 0.30; 95% CI -1.36 to 1.96). Two studies not providing data for meta-analysis showed a significant effect of treatment.Any drug use at < 12 months: the results favoured combined intervention (RR 0.76; 95% CI 0.64 to 0.89, one study, 6362 participants).Only one study assessed the effect of a knowledge-focused intervention on drug use and found no effect. The types of comparisons and the programmes assessed in the other two groups of studies were very heterogeneous and difficult to synthesise.

AUTHORS' CONCLUSIONS

School programmes based on a combination of social competence and social influence approaches showed, on average, small but consistent protective effects in preventing drug use, even if some outcomes did not show statistical significance. Some programmes based on the social competence approach also showed protective effects for some outcomes.Since the effects of school-based programmes are small, they should form part of more comprehensive strategies for drug use prevention in order to achieve a population-level impact.

Effects of a school-based prevention programme on smoking in early adolescence: a 6-month follow-up of the 'Eigenstandig werden' cluster randomised trial

OBJECTIVES

To test the effects of a school-based prevention programme on students' smoking-related behaviour, attitudes and knowledge 6 months after implementation over 2 school-years has ended.

DESIGN

Two-arm prospective cluster randomised controlled trial with a follow-up survey 6 months after end of programme implementation, that is, 26 months after baseline.

SETTING

45 public secondary schools from four federal states in Germany (Bremen, Hesse, North Rhine-Westphalia, Schleswig-Holstein).

PARTICIPANTS

A total of 3444 students from 172 classes with a mean age of 10.37 years (SD=0.59) and 47.9% girls at baseline. Analysis sample with follow-up up data merged to baseline data comprises 2513 datasets (73%).

INTERVENTION

'Eigenständig werden 5+6', a school-based prevention programme for grades 5 and 6 to enhance substance-specific and general life skills, consisting of 14 units (à 90 min) and two workshops (4-6 h) being taught over a time period of 2 school-years by trained teachers.

OUTCOME MEASURES

Lifetime and current smoking, incidence of smoking in baseline never smokers, smoking-related knowledge, attitudes, perceived norms of smoking and self-efficacy to refuse cigarette offers were assessed in students.

RESULTS

6 months after the end of programme implementation, students of intervention classes showed significantly lower rates for lifetime smoking (adjusted OR=0.63; 95% CI 0.41 to 0.96; p=0.026) and incidence of smoking (adjusted OR=0.66; 95% CI 0.43 to 1.00; p=0.047), a higher increase of smoking-related knowledge (adjusted β=9.38; 95% CI 6.73 to 12.04; p<0.001) and a greater change in attitudes towards a more critical perception of risks and disadvantages of smoking (adjusted β=0.10; 95% CI 0.03 to 0.16; p=0.002). No group differences were found for current smoking, perceived norms of smoking and self-efficacy to refuse cigarette offers.

CONCLUSIONS

Participation in the school-based prevention programme 'Eigenständig werden 5+6' may have small effects on smoking behaviour and attitudes and a moderate effect on smoking-related knowledge.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN99442407.