This study examined how perceptions of student smoking in the school environment and the actual smoking rate among senior students at a school are related to smoking onset. Multilevel logistic regression analysis was used to examine correlates of ever smoking in a sample of 4,286 grade 6 and 7 students from 57 elementary schools in Ontario, Canada. Students are at increased risk for smoking if they (a) often see students smoking near their school, (b) report that students at their school smoke where they are not allowed, and (c) attend a school with a relatively high senior student smoking rate. Each 1% increase in the smoking rate among grade 8 students increased the odds that a student in grades 6 or 7 was an ever smoker versus never smoker (odds ratio, 1.05; 95% confidence interval, 1.02-1.08). A low-risk student (no family or friends who smoke) was over twice as likely to try smoking if he/she attended a high-risk school. Prevention programs should target both at-risk schools and at-risk students, and strongly enforced policies preventing students from smoking on or near school property should be implemented.

Preventing young people from starting to smoke is critical for cancer control. The Theory of Triadic Influence (1) posits that factors from three different levels of context can influence youth smoking onset: individual characteristics (e.g., age and gender), characteristics in the immediate social environment surrounding youth (e.g., friends and family members), and characteristics in the broader social environment surrounding youth (e.g., school community). Understanding how factors from these contexts influence smoking onset can guide the development and implementation of new prevention initiatives.

Much research has examined the influence of individual characteristics and characteristics in the immediate social environment (2-4). Few studies have examined how school characteristics are related to youth smoking behavior (5). Considering that smoking rates vary across schools (5, 6) and that the variation is not caused by differences in student characteristics (6), it is important to identify the influential school characteristics associated with that variability.

Recent research has identified two influential school characteristics related to youth smoking. The first is school-level social modeling characteristics (7-10). For instance, smoking initiation is more likely to occur in schools with higher smoking rates in the senior student population (7-9). The second is school smoking restrictions (11-15). For instance, strong enforcement of school smoking restrictions is related to lower levels of student smoking (12-15).

The 1994 Ontario Tobacco Control Act banned smoking in school buildings and on school property in all publicly funded schools in Ontario, Canada (16). However, wide variation in the enforcement of these restrictions exists (17). As such, student perceptions of school smoking restrictions may have more influence on smoking behavior than the actual presence of a restriction. Furthermore, the number of smokers at a school may also influence student perceptions of school smoking restrictions because awareness of restrictions would partially depend on the prevalence of smokers affected by the restrictions (18).

The purpose of this study was to extend findings to a younger cohort and develop a more nuanced understanding of these phenomena by examining how the combination of (a) the prevalence of grade 8 students who smoke at a school and (b) student perceptions of smoking restrictions might interact to influence early initiation of smoking among younger students.

Design

This study used cross-sectional elementary school data (grades 6-8) from the School Smoking Profile Project (details have been described previously; ref. 11). The School Smoking Profile is a data collection system using machine-readable questionnaires to measure tobacco use behavior and potential determinants of tobacco use of whole-school samples.

Procedure

The School Smoking Profile was administered to students at 57 elementary schools (grades 6-8) in the province of Ontario, Canada. Passive consent was used to reduce demands on schools and to increase participation rates. The researcher informed the parents of the students via mail and asked them to call a toll-free phone number to their child's school if they declined participation. The University of Waterloo Office of Research Ethics approved all procedures, including passive consent.

Participants

There were 7,044 grade 6, 7, and 8 students in the 57 elementary schools eligible to participate in the survey. Overall, 91.3% (n = 6,431) of eligible students completed the School Smoking Profile. Missing respondents resulted from absenteeism on the day of the survey (6.1%) and parent/student refusal (2.6%).

Measures

Outcome Variables. Never smokers were defined as students who reported that they had never smoked a cigarette, not even a puff. Ever smokers were defined as students who reported that they had smoked a whole cigarette.

Predictor Variables. The validity and reliability of these measures has been reported previously (7-9, 11, 12).

Social Influences in the Broader School Environment. The senior student school-level smoking rate was operationally defined as the prevalence of grade 8 students in the school who reported that they were ever smokers and had smoked more than once in the 30 days before the survey (i.e., current smoker).

Student Perceptions of Smoking in the School Environment. Student perceptions of smoking at school were measured by asking students if they often see students smoking near their school (true or usually true/usually false or false), if their school has clear rules about smoking (true or usually true/usually false or false), if students at their school get into trouble for breaking smoking rules (true or usually true/usually false or false), and if students at their school smoke where they are not allowed (a lot or some/a few or none).

Social Influences in the Immediate Social Environment. Parental smoking was measured by asking students if they had a father who smoked (yes/no) or mother who smoked (yes/no). Sibling smoking was measured by asking students if they had an older brother or older sister who smoked (yes/no). Close friend smoking behavior was measured by asking students how many of their five closest friends smoked cigarettes (0-5).

Low-Risk Student. If a student had no close friends or family members who smoked, he/she was classified as a “low-risk” student.

High-Risk School. If a school had an above average grade 8 student smoking rate compared with the other 57 elementary schools, it was classified as a “high-risk” school.

Analyses

First, a two step multilevel logistic regression analysis modeling procedure was used to differentiate ever smokers from never smokers. In step 1, a model was developed to test if the school-level differences in the odds of being either an ever smoker or never smoker were random or fixed. In step 2, a model was developed to examine the direct effect of the senior student smoking rate at a school and the direct effects of student perceptions of smoking in the school environment, controlling for the smoking behavior of family and friends, age, and gender. Second, multilevel logistic regression analysis was used to examine if a “low-risk” student was at increased risk for ever smoking if he/she attended a “high-risk” school. Statistical analyses were conducted with MLwiN Version 1.1 (19).

Demographics

The sample contained 2,758 grade 8 students and 4,286 students in grades 6 or 7 within the 57 schools. Of the grade 6 and 7 students, 282 (6.6%) were classified as ever smokers and 3,615 (84.3%) were classified as never smokers; the remaining 389 (9.1%) students reported that they had tried a puff of a cigarette but had not smoked a full cigarette and were excluded from the analysis. This distribution is consistent with 2002 data from the Canadian Youth Smoking Survey (20). Average age was 12.7 (±0.7) years and the sample was 51.2% female. Among all never smokers and ever smokers, 14.4% reported that they often see students smoking near their school, 43% reported that their school has clear rules about smoking, 62.1% reported that students at their school get in trouble for breaking the school smoking rules, and 10.8% reported that students at their school smoke where they are not allowed. A summary of school, family, and friend influences is presented in Table 1. The average senior student smoking rate among the grade 8 students in the 57 elementary schools was 9.5% (range, 0-39%). Cameron et al. (9) reported a similar distribution.

Table 1.

Descriptive statistics for the sample of students in grades 6 and 7 who are ever smokers (n = 282) and never smokers (n = 3,615)

CharacteristicEver smokers
Never smokers
% (n)% (n)
Gender   
    Male 57.3 (161) 48.1 (1,730) 
    Female 42.7 (120) 51.9 (1,867) 
Age   
    11 23.4 (66) 40.6 (1,467) 
    12 57.5 (162) 50.4 (1,823) 
    13 16.7 (47) 8.8 (318) 
    14 2.4 (6) 0.2 (4) 
Father smokes   
    Yes 68.3 (192) 46.7 (1,684) 
    No 31.7 (89) 53.3 (1,920) 
Mother smokes   
    Yes 65.8 (185) 36.6 (1,322) 
    No 34.2 (96) 63.4 (2,288) 
Older brother smokes   
    Yes 22.5 (63) 5.8 (209) 
    No 77.5 (217) 94.2 (3,395) 
Older sister smokes   
    Yes 17.4 (49) 4.3 (156) 
    No 82.6 (232) 95.7 (3,446) 
Number of close friends who smoke   
    None 30.2 (84) 90.3 (3,255) 
    1 16.5 (46) 5.8 (210) 
    2 15.8 (44) 2.1 (74) 
    3 17.3 (48) 1.1 (40) 
    4 6.5 (18) 0.4 (15) 
    5+ 13.7 (38) 0.3 (12) 
Often sees students smoking near their school   
    True/usually true 33.3 (90) 12.9 (455) 
    Usually false/false 66.7 (180) 87.1 (3,074) 
School has clear rules about smoking   
    True/usually true 41.5 (113) 43.1 (1,527) 
    Usually false/false 58.5 (159) 56.9 (2,015) 
Students get into trouble for breaking smoking rules   
    True/usually true 66.3 (181) 61.8 (2,191) 
    Usually false/false 33.7 (92) 38.2 (1,353) 
Students at school smoke where they are not allowed   
    A lot/some 33.3 (89) 9.1 (312) 
    A few/none 66.7 (178) 90.9 (3,135) 
CharacteristicEver smokers
Never smokers
% (n)% (n)
Gender   
    Male 57.3 (161) 48.1 (1,730) 
    Female 42.7 (120) 51.9 (1,867) 
Age   
    11 23.4 (66) 40.6 (1,467) 
    12 57.5 (162) 50.4 (1,823) 
    13 16.7 (47) 8.8 (318) 
    14 2.4 (6) 0.2 (4) 
Father smokes   
    Yes 68.3 (192) 46.7 (1,684) 
    No 31.7 (89) 53.3 (1,920) 
Mother smokes   
    Yes 65.8 (185) 36.6 (1,322) 
    No 34.2 (96) 63.4 (2,288) 
Older brother smokes   
    Yes 22.5 (63) 5.8 (209) 
    No 77.5 (217) 94.2 (3,395) 
Older sister smokes   
    Yes 17.4 (49) 4.3 (156) 
    No 82.6 (232) 95.7 (3,446) 
Number of close friends who smoke   
    None 30.2 (84) 90.3 (3,255) 
    1 16.5 (46) 5.8 (210) 
    2 15.8 (44) 2.1 (74) 
    3 17.3 (48) 1.1 (40) 
    4 6.5 (18) 0.4 (15) 
    5+ 13.7 (38) 0.3 (12) 
Often sees students smoking near their school   
    True/usually true 33.3 (90) 12.9 (455) 
    Usually false/false 66.7 (180) 87.1 (3,074) 
School has clear rules about smoking   
    True/usually true 41.5 (113) 43.1 (1,527) 
    Usually false/false 58.5 (159) 56.9 (2,015) 
Students get into trouble for breaking smoking rules   
    True/usually true 66.3 (181) 61.8 (2,191) 
    Usually false/false 33.7 (92) 38.2 (1,353) 
Students at school smoke where they are not allowed   
    A lot/some 33.3 (89) 9.1 (312) 
    A few/none 66.7 (178) 90.9 (3,135) 

Multilevel Analysis of Ever Smoking

In step 1, significant [σ2μ0 = 0.62(0.19), P < 0.001] between-school random variation was found. The school a student attended was very important; school-level differences accounted for 45.2% of the variability in the odds of being an ever smoker versus a never smoker.

Table 2 displays the results of step 2. Each 1% increase in the smoking rate among senior students increased the odds that a student in grade 6 or 7 was an ever smoker versus never smoker (Fig. 1). Figure 1 also illustrates the significant contextual interaction between the senior student smoking rate in the school environment and a student's report about often seeing students smoking near the school; the senior student smoking rate at a school had a larger negative influence on students who reported that they do not often see students smoking near their school. The odds of a student being an ever smoker also increased if (a) he/she reported often seeing students smoking near their school (odds ratio, 2.63; 95% confidence interval, 1.28-5.37) and (b) he/she reported that students at school smoke where they are not allowed (odds ratio, 2.23; 95% confidence interval, 1.05-4.75).

Table 2.

A multilevel analysis of student smoking behavior in the school environment and the likelihood of being an ever smoker versus a never smoker

ParameterStandardized β (SE)αOdds ratio (95% CI)
Intercept −6.05 (0.43)   
Student perceptions of smoking at school    
    Often sees students smoking near their school 0.966 (0.365) P < 0.01 2.63 (1.20-5.37) 
    School has clear rules about smoking −0.013 (0.337) ns 0.99 (0.51-1.91) 
    Students get into trouble for breaking smoking rules −0.021 (0.343) ns 2.63 (1.28-5.37) 
    Students at school smoke where they are not allowed 0.804 (0.385) P < 0.05 2.23 (1.05-4.75) 
Actual prevalence of older student smoking    
    Senior student smoking rate 0.048 (0.015) P < 0.01 1.05 (1.02-1.08) 
Contextual interactions    
    Often sees students smoking near their school by senior student smoking rate −0.035 (0.014) P < 0.05 0.97 (0.94-0.99) 
    School has clear rules about smoking by senior student smoking rate −0.013 (0.013) ns 0.99 (0.96-1.01) 
    Students get into trouble for breaking smoking rules by senior student smoking rate 0.013 (0.014) ns 1.01 (0.99-1.04) 
    Students at school smoke where they are not allowed by senior student smoking rate −0.017 (0.014) ns 0.98 (0.96-1.01) 
Random    
    School-level random variance σ2μ0 = 0.62 (0.19)   
    Student-level random variance σ2e0 = 0.75 (0.02)   
ParameterStandardized β (SE)αOdds ratio (95% CI)
Intercept −6.05 (0.43)   
Student perceptions of smoking at school    
    Often sees students smoking near their school 0.966 (0.365) P < 0.01 2.63 (1.20-5.37) 
    School has clear rules about smoking −0.013 (0.337) ns 0.99 (0.51-1.91) 
    Students get into trouble for breaking smoking rules −0.021 (0.343) ns 2.63 (1.28-5.37) 
    Students at school smoke where they are not allowed 0.804 (0.385) P < 0.05 2.23 (1.05-4.75) 
Actual prevalence of older student smoking    
    Senior student smoking rate 0.048 (0.015) P < 0.01 1.05 (1.02-1.08) 
Contextual interactions    
    Often sees students smoking near their school by senior student smoking rate −0.035 (0.014) P < 0.05 0.97 (0.94-0.99) 
    School has clear rules about smoking by senior student smoking rate −0.013 (0.013) ns 0.99 (0.96-1.01) 
    Students get into trouble for breaking smoking rules by senior student smoking rate 0.013 (0.014) ns 1.01 (0.99-1.04) 
    Students at school smoke where they are not allowed by senior student smoking rate −0.017 (0.014) ns 0.98 (0.96-1.01) 
Random    
    School-level random variance σ2μ0 = 0.62 (0.19)   
    Student-level random variance σ2e0 = 0.75 (0.02)   

NOTE: 1 = ever smoker (n = 282); 0 = never smoker (n = 3,615). Controlling for parental and sibling smoking, close friend smoking, gender, and age.

Abbreviations: CI, confidence interval; ns, not significant.

Figure 1.

Model-based estimated odds ratio for being an ever smoker versus a never smoker as a function of the senior student smoking rate at a school and often seeing students smoking near the school.

Figure 1.

Model-based estimated odds ratio for being an ever smoker versus a never smoker as a function of the senior student smoking rate at a school and often seeing students smoking near the school.

Close modal

Low-Risk Students in High-Risk Schools

Overall, 1,400 (32.7%) students in grades 6 and 7 were classified as low-risk students, and 23 (40.3%) schools were classified as high-risk schools (grade 8 student smoking rate greater than 9.5%). The odds of a low-risk student being an ever smoker increased if he/she attended a high-risk school (odds ratio, 2.35; 95% confidence interval, 1.75-3.15) even when controlling for student perceptions of smoking in the school environment, age, and gender.

This study found that ever smoking was more likely to occur among grade 6 and 7 students who (a) were in a school with a high prevalence of smokers among grade 8 students, (b) reported often seeing students smoking near their school, or (c) reported that students at their school smoke where they are not allowed. Students typically thought of as low-risk for smoking were more likely to smoke if they attended a high-risk school.

Influence of the School Environment

Characteristics of the school a student attends can influence the risk for smoking. If an student in grades 6 or 7 attends a school with a high prevalence of grade 8 students who smoke, he/she is more likely to be an ever smoker than a similar student attending a school with a lower prevalence of grade 8 students who smoke. This finding is consistent with research examining advanced smoking behavior among high school students (7, 8). As the prevalence of smoking among older students at a school increases, the chance of developing friendships with an older smoker may increase (21, 22), smoking may seem more normative and acceptable (23), more social sources of cigarettes might exist (24), and it may seem that social prestige or popularity could be improved by smoking (25). These factors could make a younger student more apt to try smoking (26).

It seems that a school with a large number of older students who smoke creates a high-risk environment for smoking among the younger students at that school. This finding supports existing research (7-9). In addition, the finding that low-risk students in high-risk schools are more than twice as likely to have tried smoking than their counterparts in low-risk schools suggests that characteristics within the school environment affect even the youth who are least vulnerable to smoking initiation. These findings provide empirical evidence supporting the current theoretical literature (1); characteristics of the school a student attends may be risk factors for smoking onset above and beyond the characteristics of the student.

Influence of Student Perceptions of Smoking in the School Environment

Student perceptions of smoking in their school environment can also influence the risk for smoking. If an elementary school student reports that they often see students smoking near their school or that students at their school smoke where they are not allowed, he/she is more likely to be an ever smoker than a similar student who does not report seeing student smoking near the school or where they are not allowed. This is also consistent with existing evidence for high school students (11, 12), and provides additional evidence that the enforcement of school smoking restrictions is an effective tobacco control measure among youth (12-15).

The use of students' perceptions of school smoking policy is a strength of this study when compared with studies that have used an administrator or teacher's report to define the school smoking policy (14, 15). Regardless of the actual level of enforcement, the perception that smoking restrictions are enforced provides an unequivocal message about the unacceptability of smoking (15).

Implications for Practice and Research

These findings suggest that it might be beneficial to expand the jurisdiction covered by school smoking restrictions to include the property surrounding a school. When the 1994 Tobacco Control Act banned student smoking on school property in Ontario, it pushed most student smoking from designated smoking areas located out of sight of most students, to highly visible areas in front of schools, at least in high school settings (17). This shift can inadvertently make smoking more visible and, hence, socially desirable to nonsmoking students (27). In response, research is required to determine if prohibiting students and adults from smoking in areas visible from a school impacts youth smoking onset and progression. Evidence from a case study where student smoking has been pushed further afield and out of site does support benefits of these actions (28). However, this approach does require considerably more commitment on the part of people responsible for enforcement (e.g., school staff) and may require buy-in from school neighbors to operate effectively.

These findings also confirm that there is a need to target high-risk elementary schools with prevention activities (9). By targeting high-risk schools, intensive prevention programs could be implemented in the schools that are putting students at the greatest risk for smoking. For example, low-risk students in grades 6 and 7 were over twice as likely to be ever smokers if they attended a school with an above average prevalence of grade 8 students who smoke. However, educators and public health personnel need school-level data to be able to target their interventions to these high-risk settings. Such targeting can also extend limited education and public health funds for intervention by reducing the number of schools that require intensive intervention.

The utility of the methodology used may also have application to other student health issues, such as physical inactivity and unhealthy eating; other key risk factors for cancer (29). A surveillance system that could facilitate identification of high-risk settings across multiple risk behaviors would further help rationalize costs of both prevention program planning and intervention. Indeed, a useful research study would answer whether schools that provide risky environments for one type of behavior also contribute to risk for other behaviors.

Limitations

The cross-sectional design of this study precludes examination of temporal relationships among variables. For instance, it would be illuminating to know how patterns of student smoking surrounding a school influence the number of friendships a young person develops with smokers and how entering a high-risk school affects the emergence of smoking friendships. Longitudinal data are required to address such questions. Data were also based on self-reports so the validity of the responses may be questioned. However, the measures in the School Smoking Profile have been previously shown to be reliable and valid; honest reporting was encouraged by ensuring confidentiality during data collection, and some students were asked to provide preannounced saliva samples for biochemical validation to further encourage honest reporting.

This study confirms that social modeling of smoking behavior in the school environment is related to smoking onset in elementary school students. A school with a large number of older students who smoke creates a high-risk environment for smoking among the younger students at that school, above and beyond the characteristics of the student. Furthermore, low-risk youth in grades 6 and 7 are at significantly greater risk of smoking if they attend an elementary school with a relatively high prevalence of smoking among grade 8 students. Prevention programs should target both at-risk schools and at-risk students, and strongly enforced policies preventing students from smoking on or near school property should be implemented.

Grant support: Social Science and Humanities Research Council, and Centre for Behavioural Research and Program Evaluation, Canadian Cancer Society/National Cancer Institute of Canada.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

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