School-based programmes for preventing smoking

Thomas RE, McLellan J, Perera R. School-based programmes for preventing smoking. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD001293. DOI: 10.1002/14651858.CD001293.pub3.

Abstract

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, PsyclNFO, 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.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18.

Dobbins M, Husson H, Decorby K, Larocca RL.
Cochrane Database Syst Rev. 2013 Feb 28;2:CD007651. doi: 10.1002/14651858.CD007651.pub2.

BACKGROUND: The World Health Organization (WHO) estimates that 1.9 million deaths
worldwide are attributable to physical inactivity and at least 2.6 million deaths
are a result of being overweight or obese. In addition, WHO estimates that
physical inactivity causes 10% to 16% of cases each of breast cancer, colon, and 
rectal cancers as well as type 2 diabetes, and 22% of coronary heart disease and 
the burden of these and other chronic diseases has rapidly increased in recent
decades.
OBJECTIVES: The purpose of this systematic review was to summarize the evidence
of the effectiveness of school-based interventions in promoting physical activity
and fitness in children and adolescents.
SEARCH METHODS: The search strategy included searching several databases to
October 2011. In addition, reference lists of included articles and background
papers were reviewed for potentially relevant studies, as well as references from
relevant Cochrane reviews. Primary authors of included studies were contacted as 
needed for additional information.
SELECTION CRITERIA: To be included, the intervention had to be relevant to public
health practice (focused on health promotion activities), not conducted by
physicians, implemented, facilitated, or promoted by staff in local public health
units, implemented in a school setting and aimed at increasing physical activity,
included all school-attending children, and be implemented for a minimum of 12
weeks. In addition, the review was limited to randomized controlled trials and
those that reported on outcomes for children and adolescents (aged 6 to 18
years). Primary outcomes included: rates of moderate to vigorous physical
activity during the school day, time engaged in moderate to vigorous physical
activity during the school day, and time spent watching television. Secondary
outcomes related to physical health status measures including: systolic and
diastolic blood pressure, blood cholesterol, body mass index (BMI), maximal
oxygen uptake (VOmax), and pulse rate.
DATA COLLECTION AND ANALYSIS: Standardized tools were used by two independent
reviewers to assess each study for relevance and for data extraction. In
addition, each study was assessed for risk of bias as specified in the Cochrane
Handbook for Systematic Reviews of Interventions. Where discrepancies existed,
discussion occurred until consensus was reached. The results were summarized
narratively due to wide variations in the populations, interventions evaluated,
and outcomes measured.
MAIN RESULTS: In the original review, 13,841 records were identified and
screened, 302 studies were assessed for eligibility, and 26 studies were included
in the review. There was some evidence that school-based physical activity
interventions had a positive impact on four of the nine outcome measures.
Specifically positive effects were observed for duration of physical activity,
television viewing, VO max, and blood cholesterol. Generally, school-based
interventions had little effect on physical activity rates, systolic and
diastolic blood pressure, BMI, and pulse rate. At a minimum, a combination of
printed educational materials and changes to the school curriculum that promote
physical activity resulted in positive effects.In this update, given the addition
of three new inclusion criteria (randomized design, all school-attending children
invited to participate, minimum 12-week intervention) 12 of the original 26
studies were excluded. In addition, studies published between July 2007 and
October 2011 evaluating the effectiveness of school-based physical interventions 
were identified and if relevant included. In total an additional 2378 titles were
screened of which 285 unique studies were deemed potentially relevant. Of those
30 met all relevance criteria and have been included in this update. This update 
includes 44 studies and represents complete data for 36,593 study participants.
Duration of interventions ranged from 12 weeks to six years.Generally, the
majority of studies included in this update, despite being randomized controlled 
trials, are, at a minimum, at moderate risk of bias. The results therefore must
be interpreted with caution. Few changes in outcomes were observed in this update
with the exception of blood cholesterol and physical activity rates. For example 
blood cholesterol was no longer positively impacted upon by school-based physical
activity interventions. However, there was some evidence to suggest that
school-based physical activity interventions led to an improvement in the
proportion of children who engaged in moderate to vigorous physical activity
during school hours (odds ratio (OR) 2.74, 95% confidence interval (CI), 2.01 to 
3.75). Improvements in physical activity rates were not observed in the original 
review. Children and adolescents exposed to the intervention also spent more time
engaged in moderate to vigorous physical activity (with results across studies
ranging from five to 45 min more), spent less time watching television (results
range from five to 60 min less per day), and had improved VOmax (results across
studies ranged from 1.6 to 3.7 mL/kg per min). However, the overall conclusions
of this update do not differ significantly from those reported in the original
review.
AUTHORS' CONCLUSIONS: The evidence suggests the ongoing implementation of
school-based physical activity interventions at this time, given the positive
effects on behavior and one physical health status measure. However, given these 
studies are at a minimum of moderate risk of bias, and the magnitude of effect is
generally small, these results should be interpreted cautiously. Additional
research on the long-term impact of these interventions is needed.

School Health Guidelines to Promote Healthy Eating and Physical Activity

 www.cdc.gov/healthyyouth/npao/strategies.htm

Schools play a critical role in improving the dietary and physical activity behaviors of children and adolescents. Schools can create environments supportive of students’ efforts to eat healthy and be active by implementing policies and practices that support healthy eating and regular physical activity and by providing opportunities for students to learn about and practice these behaviors.

CDC synthesized research and best practices related to promoting healthy eating and physical activity in schools, culminating in nine guidelines. These guidelines were informed by the Dietary Guidelines for Americans,¹ the Physical Activity Guidelines for Americans,² and the Healthy People 2020 objectives related to healthy eating and physical activity among children, adolescents, and schools.³ The guidelines serve as the foundation for developing, implementing, and evaluating school-based healthy eating and physical activity policies and practices for students.

Each of the nine guidelines is accompanied by a set of implementation strategies developed to help schools work towards achieving each guideline. Although the ultimate goal is to implement all nine guidelines included in this document, not every strategy will be appropriate for every school, and some schools, due to resource limitations, might need to implement the guidelines incrementally.

The health of students is linked to their academic success. Both physical activity and healthy eating may help improve academic achievement.^4–7

Healthy eating and regular physical activity play a powerful role in preventing obesity and chronic diseases, including heart disease, cancer, and stroke — the three leading causes of death among adults aged 18 years or older.^8–12

Efficacy of a School-Based Childhood Obesity Intervention Program in a Rural Southern Community: TEAM Mississippi Project.

Greening L, Harrell KT, Low AK, et al. Obesity (Silver Spring). 2011 Jun;19(6):1213-9. Epub 2011 Jan 13
Abstract
A healthy lifestyle school-based obesity intervention was evaluated in a rural southern community where the rate of obesity ranks as the highest. School-age children (N = 450) ranging from 6 to 10 years of age (M(age) = 8.34) participated in monthly physical activity and nutritional events during a 9-month academic year. The children`s nutritional knowledge, number of different physical activities, fitness level, dietary habits, waist circumference, BMI percentile, and percentage body fat were measured pre- and postintervention. Changes on these measures were compared to students in a school employing the school system`s standard health curriculum. Regression analyses with residualized change scores revealed that the intervention school showed statistically significant improvement in percentage body fat, physical activity, performance on fitness tests, and dietary habits compared to the control school. There was no evidence of differences in outcomes based on gender or ethnicity/race. With rates of obesity and overweight reaching 50% in southern rural communities, intervening early in development may offer the best outcome because of the difficulties with changing lifestyle behaviors later in adulthood. A population-based approach is recommended over a targeted approach to cultivate a culture of healthy lifestyle behaviors when children are developing their health-care habits. Evidence suggests that both boys and girls, and African-American and white children can benefit equally from such interventions.