Health Education Research Advance Access originally published online on July 21, 2005
Health Education Research 2006 21(1):108-115; doi:10.1093/her/cyh047
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Is there a relation between school smoking policies and youth cigarette smoking knowledge and behaviors?
1 Social and Behavioural Research in Cancer Group, Department of Preventive and Social Medicine and 2 Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand
3 Correspondence to: H. Darling; E-mail: helen.darling{at}stonebow.otago.ac.nz
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Abstract |
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To comply with workplace legislation, New Zealand schools are required to have policies regarding tobacco smoking. Many schools also have policies to prevent tobacco use by students, including education programmes, cessation support and punishment for students found smoking. This paper investigated the associations between school policies and the prevalence of students' cigarette smoking. Furthermore, we investigated the association between school policy and students' tobacco purchasing behavior, knowledge of health effects from tobacco use and likelihood of influencing others not to smoke. Data were obtained from a self-report survey administered to 2658 New Zealand secondary school students and staff from 63 schools selected using a multi-stage sampling procedure. Components of school policy were not significantly associated with smoking outcomes, health knowledge or health behavior, and weakly related to a punishment emphasis and students advising others to not smoke. Similarly, weak associations were found between not advising others to not smoke and policies with a punishment emphasis as well as smoke-free environments. The results suggest that having a school tobacco policy was unrelated to the prevalence of tobacco use among students, tobacco purchasing behavior and knowledge of the negative health effects of tobacco.
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Introduction |
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In order to further the public health goal of reducing cigarette smoking among youth, it has become commonplace to implement prevention programmes within the school environment. As most adolescents attend school, school settings provide a means of reaching a high proportion of young people with relative ease. Yet schools vary considerably in terms of policies to prevent cigarette smoking and the provision of education about smoking. A recent study demonstrated variation in the content of school policies in New Zealand, although most schools provided some education intended to prevent tobacco smoking as required by the Health and Physical Education curriculum (Ministry of Education, 1999
), many schools included education about tobacco in sanctions imposed on students caught smoking and these sanctions were documented in school smoking policies (Darling and Reeder, 2003). In addition to educational programmes, preventive strategies may include sanctions imposed on students caught smoking and the provision of smoke-free environments with smoke-free adult role models. Examination of the effect of the school environment on youth tobacco use is complex, and may include the effects of school policies, the rigor of their implementation, and the provision and content of school-based education and cessation programmes. This paper aims to investigate the relation between school policies and students' cigarette smoking (1), health behaviors (specifically, tobacco purchasing behavior) (2), knowledge of the health effects of tobacco use (3), and likelihood of trying to influence others not to smoke (4).
Student smoking policies are intended to prevent or delay tobacco use by youth; generally, school policies are designed to reduce exposure of employees to second-hand smoke (Griesbach et al., 2002). Nevertheless, policies that encourage smoke-free environments and promote smoke-free adult role models are considered of use in preventing or delaying tobacco use by youth (Kannas and Schmidt, 2001).
An earlier study, which examined the effect of components of smoking policies on youth tobacco use, found punitive measures to be ineffective, whereas policies that focused on prevention through education and cessation support were associated with significantly lower levels of smoking (Pentz et al., 1995). More recently, mixed results have been reported for school smoking prevention policies. In one study, although the existence of school policies that banned smoking was not related to smoking uptake, when there was evidence that these policies were enforced they were effective in reducing uptake, regardless of smoking stage (Wakefield et al., 2000). Similarly, school-level compliance with no-smoking rules demonstrated a strong association with decreased probability of smoking in a sample of Spanish adolescents (Pinilla et al., 2002). An association between the strength of the enforced policy and smoking prevalence has been observed, with lower prevalence of daily smoking among students attending schools with enforced policy and school-wide smoking bans (Moore et al., 2001). However, successful implementation of school-wide smoking bans may be compromised by the provision of designated smoking areas for staff. In one study, schools with such areas were more likely to report difficulties in implementing smoking bans and have a perception that the ban would not reduce youth smoking (Pickett et al., 1999). Additionally, young people appear sensitive to the hypocrisy of observing school staff smoking despite rules to prevent students smoking (Crawford, 2001) and this may influence the smoking behavior of students. Difficulties in instituting policies appear widespread (Pentz et al., 1997). It has been suggested that compulsory implementation would assist school staff in enforcing policies (Hartland et al., 1998); however, even where school smoking policies are mandatory they have not necessarily produced smoke-free environments (Reeder and Glasgow, 2000; Darling and Reeder, 2003). School smoking policies and bans have had mixed results, but there appears to be agreement that school environments should be smoke-free if only to provide smoke-free role models and consistency with health education (Pickett et al., 1999; Booth-Butterfield et al., 2000; Reeder and Glasgow, 2000; Darling and Reeder, 2003).
Thomas (Thomas, 2003) described five theoretical perspectives for school-based tobacco education and reviewed randomized controlled trials (RCTs) of school programmes using this framework. The one social competence programme that met criteria for review demonstrated a protective effect for boys at 2-year follow-up (Kellam and Anthony, 1998). The remaining programme types were excluded from the review of RCTs on the basis of poor study quality (Thomas, 2003). The inability of schools to sustain complex and costly preventive programmes, and the use of adult models rather than youth appropriate programmes may explain some of the disappointing results of school-based programmes (Aveyard et al., 1999; Reid, 1999). Additionally, tobacco education may not be seen as a high priority by teaching staff (Distefan et al., 2000). In summary, it would appear that, at best, school-based education programmes might only delay smoking initiation (Reid, 1999).
The apparent influence of peers on within-school smoking prevalence may be a result of the development of a pro-smoking environment, where more children smoke as a result of poorly enforced policy, rather than the influence of peers who smoke (Aveyard et al., 2004). Moreover, smoking behavior may eventually determine peer group membership; students who smoke being more likely to have peers who smoke (Crawford et al., 2002) or vice versa (Lucas and Lloyd, 2000). Analysis of a peer support programme, designed to prevent tobacco and alcohol use, reported that the peer-based programme had no effect on knowledge, attitude or behavior (Webster et al., 2002), although some researchers have found an association between school drug policies and increased confidence of students to ask others to not smoke within the school environment (Hamilton et al., 2003). Similarly, an intervention to address peer pressure as a means of preventing tobacco use was ineffective at 1-year follow-up (Crone et al., 2003). There are differences between formal peer-based programmes and naturally occurring peer relationships, however, and other studies have demonstrated a positive association between peers and smoking initiation (De Vries et al., 2003; Vink et al., 2003).
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Methods |
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Sample
We analyzed data from the New Zealand Health Sponsorship Council's (HSC) biennial Youth Lifestyle Study (YLS) of Year 10 and Year 12 students (overall mean age 15.0 years). The YLS used multi-stage cluster sampling. Briefly, the first stage was the selection of six geographical regions to represent the North and South Islands of New Zealand. The second stage involved the random selection of schools within each region from school lists provided by the Ministry of Education. Finally, classes were randomly selected from school lists provided by participating schools. A total of 82 schools and 3434 students participated in the 2002 survey. Most students (n = 2388) attended 56 coeducational schools, but 552 girls and 494 boys each attended 13 single-sex institutions. New Zealand schools are assigned a decile rating reflecting the socioeconomic status of the students attending the school. Deciles are calculated using school and census data, including household income for the school area, parental educational qualifications and, until recently, ethnicity. Deciles are ranked from 1 (lowest) through 10 (highest). A high decile rating reflects a higher socioeconomic status of the community. Of the 82 schools selected, 23 (28.0%) were decile 1–3, 25 (30.5%) were decile 4–6 and 34 (41.5%) were decile 7–10.
School policy data were obtained from the School Smoking Policy Survey (SSPS) which was carried out in conjunction with the YLS (Darling and Reeder, 2003). Schools which participated in the YLS were invited, through the Principal, to participate in the SSPS and 81 out of 82 schools agreed. The school that refused to participate in the SSPS was a decile 2 school.
The YLS was administered by trained interviewers in school classes during May and November 2002. No personal identifying information was recorded and students were advised that their answers were anonymous.
Questionnaire and measures
In addition to routine data obtained from the Ministry of Education (school roll size, decile, composition), data were collected from each school by the interviewer, including the smoke-free status of the school (whether the school was totally smoke-free 7 days per week, 24 hours per day or whether the school provided a time when or place where smoking by staff was permitted) and the number of students absent on the day of the survey.
The questionnaire comprised five sections, in the first of which students were asked to record their demographic details (age, sex and ethnicity). Also included were questions about sources of disposable income, spending and future educational aspirations. In the second section of the YLS, interest and participation in sports and cultural activities were assessed (Richards et al., 2004). In the third section, students were asked about their use of the media, and personal access to and use of the Internet. The fourth section included questions about tobacco-related knowledge, attitudes and behaviors. Current smoking status was determined from responses to the question ‘How often do you smoke now?’. Daily smokers were those who responded ‘at least once a day’, occasional smokers those who responded ‘at least once a week’ or ‘at least once a month’ and remaining students were categorized as non-smokers. To assess purchasing behavior, students were asked ‘In the last 30 days (1 month) how did you usually get your own cigarettes?’. The nine response options included ‘I bought them from a shop’, ‘I brought them from another student’, ‘I got them from friends’ and ‘I got them from my parents’. Students were also asked ‘where do you usually smoke?’, and provided with response categories that included home, school, work and social events. To assess knowledge about health effects due to cigarette smoking, students were asked ‘Do you think cigarette smoking is harmful to your health?’, ‘Once someone has started smoking, do you think it would be difficult to quit?’ and ‘Do you think the smoke from other people's cigarettes is harmful to you?’. Response categories for these three questions were ‘definitely not’, ‘probably not’, ‘probably yes’ and ‘definitely yes’. To investigate whether they had influenced others to not smoke, students were asked ‘In the last year, have you said or done anything to influence whether other people:’ with the response categories: ‘do not smoke; smoke; I have not influenced people to smoke or not smoke’. Students were able to select only one response. The final section of the YLS contained a measure of self-concept and awareness of some of the smoke-free initiatives in New Zealand.
A separate questionnaire completed by a member of school staff, usually the school principal or teacher in charge of the Health and Physical Education curriculum (the SSPS) (Darling and Reeder, 2003) was based on an earlier survey of New Zealand primary and intermediate schools, and asked five questions regarding school smoke-free policies and practices (Reeder and Glasgow, 2000). In the remainder of the questionnaire, questions were asked about health education (specifically related to tobacco), participation in smoke-free health promotion events, access to cessation programmes and sanctions imposed on students smoking at school.
Analysis
School smoking policies were coded into four categories following Pentz et al. (Pentz et al., 1989) and entered into STATA version 8.0 (Stata, Corporation, TX). Policies were considered to have a punishment emphasis if either sanctions for students who were caught smoking were included in the policy (including ‘education’ against cigarette smoking) or the policy included definitions of behavior that would be sanctioned (e.g. caught smoking a cigarette; found in possession of cigarettes). Policies which described cessation support were considered to have a cessation focus. If prevention guidelines were included in the policy, that policy had a preventive focus. Policies that identified more than two situations in which the students were required to be smoke-free and which informed the public of the policy were designated ‘comprehensive’.
As there was wide variation in the smoking prevalence rates between schools, the data were analyzed by school rather than at the individual level. The outcome variable was the number of pupils who smoked. The size of the sample for each school was taken into account by including an offset in the models.
Negative binomial regression analysis was used to examine the association between smoking prevalence, smoking behavior in each school and school characteristics. The number of children who smoked, for instance, was the dependent variable and the characteristic of the school was the independent variable. The number of children in each school (the denominator) was used as the exposure or offset variable. The results are presented as risk ratios (RRs) with 95% confidence intervals (CIs).
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Results |
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Complete data were available for 2658 students from 63 of the 82 participating schools: 15 (23.8%) were decile 1–3, 20 (31.7%) were decile 4–6 and 28 (44.4%) were decile 7–10. Most schools (42, 66.7%) were coeducational; 13 (20.6%) female only and eight (12.7%) male only. School rolls ranged from 293 to 2503 students. The prevalence of daily smoking within each school ranged from 0 to 35.4%.
Eighteen schools were excluded from the analysis as a copy of the school smoking policy had not been received. A further school was excluded due to the high number of students absent on the survey day. Eight schools were decile 1–3, five were decile 4–6 and the remaining six were decile 7–10.
The relation between school policy and the prevalence of students' cigarette smoking is presented for three outcomes: all smokers, daily smokers and ‘school’ smokers, i.e. students who identified school as the location where they usually smoked. The prevalence of smoking by school decile is presented in Table I.
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There was a significant decreasing trend for daily smoking and smoking at school as decile increased (socioeconomic status increased) (z = 2.24, P = 0.03). There was no significant difference for overall smoking prevalence between the decile groups.
The RRs and CIs for policy components are presented in Table II. For school policies with a punishment emphasis the RR was the same as for those without this component for all smokers, and although the RR was lower for daily smokers and school smokers, these differences were not statistically significant. The RRs for the other components of school policy, when compared with the reference group (schools without the specific policy component), were not significant. There was no evidence of confounding by school decile, when the three decile categories were included in the model.
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The relation of both knowledge of health effects and purchasing behavior with policy emphasis was examined using negative binomial regression, but again no significant associations were found. Policies which had a punishment emphasis had a negative health effect for students advising others not to smoke, whereby students were 11% less likely to advise other students against smoking (RR = 0.89, CI 0.78–1.00, P = 0.049). Similarly, schools with policies which provided a smoke-free environment for students reduced the likelihood of advising others not to smoke (RR = 0.90, CI 0.81–1.00, P = 0.044).
Student perceptions of not being taught about the health effects of cigarette smoking did not differ significantly according to policy focus.
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Discussion |
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The daily smoking prevalence rates for study schools ranged from 0 to 35.4%, thereby providing sufficient variation for analysis. The possible association between the type and strength of school policy and student smoking prevalence was one aim of the current study. The significant trend towards higher smoking prevalence among lower-decile schools is consistent with other New Zealand research (Hill et al., 2003
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The intended outcome for school smoking policies and education about tobacco are to decrease the prevalence of smoking among youth. In this study the association between school policies, including health education and health knowledge, was investigated; there was no significant association and this should be viewed with concern. The New Zealand secondary school curriculum includes health education components that relate to tobacco use. The widespread implementation of broadly similar health education programmes may explain the observed lack of difference between schools that had explicit health education goals in policy and those that did not. These results are similar to a Flemish study where no association was found between health promotion policies and actual health behavior (Maes and Lievens, 2003). Similarly, policy components had no effect on the purchasing of cigarettes.
An association between having a smoke-free school environment and students influencing others to not smoke was found in this study. However, this association was not congruent with perceptions that a smoke-free environment would promote non-smoking. The effect (RR = 0.90) suggests that smoke-free environments reduce the likelihood of students encouraging others to not smoke by 10%, although this association was weak (CI 0.81–1.00).
In contrast to the findings of other studies (Moore et al., 2001), the present study failed to find an association between the strength of school policy and student smoking. Further, no significant association was found between policies which included sanctions for students caught smoking at school and the prevalence of smoking at school.
A limitation of the present study was that no data were available about policy implementation. School policy represents the intention of the governing body for the school and meets the requirements of the Education Review Office, whereas policy implementation may differ significantly from that intention and can only be verified by frequent onsite assessment. In addition, it would be of value to understand students' perspectives of policy and this is an area highlighted for further research.
In spite of unfavorable results in reviewed literature, there is a consensus that programmes to prevent adolescent tobacco use need to be incorporated into a comprehensive tobacco control initiative, including community-wide initiatives (Perry, 1992; Crawford, 2001; Griesbach et al., 2002). Despite perception that the school environment may place youth at risk of smoking, there is evidence that the prevalence of peers' smoking is not associated with daily smoking prevalence rates (Kannas and Schmidt, 2001). It is plausible that totally smoke-free environments providing a consistent health message are likely to be more effective in preventing tobacco use than any loosely implemented policy.
Prior to the implementation of amendments to legislation which required that from January 2004 all New Zealand schools must be smoke-free at all times (The Smoke-free Environments Act, 1990), school boards of trustees decided the degree to which schools would be smoke-free and the extent of smoking restrictions. The new legislation presents an opportunity to further investigate the effect of schools and the school environment on youth smoking prevalence. Although all schools will provide a totally smoke-free environment, schools will continue to individually determine policies for health education on tobacco and dealing with students who smoke.
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Acknowledgments |
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This report is based on data collected in the YLS 2002. The HSC was the primary contributor to the YLS with support from the Ministry of Health, Cancer Society of New Zealand, The Quit Group, and the Social and Behavioural Research in Cancer Group, University of Otago. A. I. R. and the Social and Behavioural Research in Cancer Group receive support from the Cancer Society of New Zealand and the University of Otago. The research was completed while H. D. was the recipient of post-graduate scholarships from the HSC and the University of Otago.
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Received on July 23, 2004; accepted on June 20, 2005
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