The European Journal of Public Health Advance Access published online on June 25, 2008
The European Journal of Public Health, doi:10.1093/eurpub/ckn054
The tobacco sales ban and tobacco purchases by adolescents: a general population study in The Netherlands
Wendy M. I. Verdonk-Kleinjan1, Ronald A. Knibbe2, Bert Bieleman3, Henk N. de Groot1 and Hein de Vries2
1 Food and Consumer Product Safety Authority (VWA), Eindhoven, The Netherlands
2 Department of Health Education and Promotion, Faculty of Health, Medicine & Life Sciences, University Maastricht, Maastricht, The Netherlands
3 Intraval, Bureau for Social-Scientific Research and Consultancy, Groningen, The Netherlands
Correspondence: Wendy M. I. Verdonk-Kleinjan, Food and Consumer Product Safety Authority (VWA), Directorate Implementation Enforcement and Surveillance, PO Box 2168, 5600 CD Eindhoven, The Netherlands, tel: +31 (0)40 – 29 11 500, fax: +31 (0)40 – 29 11 600, e-mail: wendy.verdonk-kleinjan{at}vwa.nl
Received January 28, 2008, accepted May 11, 2008
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Abstract |
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Background: The study aimed to assess the effect of the introduction on 1 January 2003 of a legal tobacco sales ban in The Netherlands on tobacco purchases by smoking and non-smoking adolescents aged <16 years. Methods: Two cross-sectional surveys were conducted among adolescents aged 13 through 15 years, one at end 1999 (n = 4751) and the other at end 2003 (n = 13 298). Results: The percentage of adolescents buying tobacco decreased significantly from 26.3% in 1999 to 10.8% in 2003 (P < 0.001). Further analysis showed that, after the ban, the proportion of smokers among buyers almost tripled [Odds Ratio (OR) = 2.9], while the likelihood of non-smokers buying tobacco decreased strongly (OR = 0.17). A difference in the pattern of purchasing tobacco also emerged after the ban. In 2003, the proportion of smokers buying at least weekly in commercial outlets was larger than in 1999. For non-smokers there was no difference between 1999 and 2003 in the proportion buying weekly. The variety of commercial outlets in which purchases were made increased among both smoking and non-smoking purchasers of tobacco. Conclusions: Implementation of the 2003 tobacco sales ban has had the (intended) effect of lowering tobacco purchases among adolescents. This was mainly due to the decrease in the likelihood of buying tobacco among those who regard themselves as a non-smoker. The decrease in buying tobacco is associated with a decrease in prevalence of smoking. The sales ban has probably contributed to a stronger decrease in prevalence of smoking.
Keywords: commercial outlets, purchasing tobacco, smoking and non-smoking adolescents, tobacco sales ban
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Introduction |
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Selling tobacco to adolescents is prohibited by law in most Western countries,1 thus discouraging smoking (onset). Up to 2003, The Netherlands was one of the few European countries without a legislative tobacco sales ban for adolescents.2 The need to discourage smoking among adolescents in The Netherlands is high because 52% of schoolchildren report to start smoking by the age of 15 years or younger and 28% report daily smoking by the age of 16 years or younger.3 This study aims to assess the effect of the introduction of a legal tobacco sales ban in the Netherlands for adolescents <16 years, on tobacco purchasing among adolescents aged 13 through 15 years.
Most studies on the effects of a ban on tobacco sales to adolescents have been conducted in the United States and Australia.4,5 Comparable studies in Europe have only been conducted in the UK, Finland and Sweden.6–10 Generally, these studies do not explore the (possible) effect of a new or changed law, but the effect of an intervention in the context of a (existing) law to improve the compliance of tobacco retailers and/or adolescents.4,5 The main conclusions from those studies are that interventions based on enforcement or on community interventions tend to be more effective than simply providing information.4,5,11 The combination of enforcement of the sales ban among retailers with fines for young adolescents in possession of tobacco is possibly even more effective.5,12,13 A few studies have investigated the implementation of a new or changed law: Rimpelä and Rainio9 found a significant decrease in the percentage of smoking adolescents who buy tobacco themselves in regular outlets and a significant increase in other points of sale, Sundh and Hagquist10 found that it was more difficult to purchase tobacco and Hinds14 found no significant change in the number of purchasers in stores and vending machines, but found that the use of friends as a source had increased significantly.
With the introduction of the sales ban in the Netherlands in 2003, the Food and Consumer Product Safety Authority (VWA) became legally liable to check compliance with the tobacco sales ban. Inspectors anonymously observed commercial outlets which adolescents use, to control for compliance, i.e. selling to minors without asking for their identification. In addition, the Tobacco Points of Sale Platform provided tobacco retailers with information about the tobacco sales ban.
This study explores the effects of implementing the 2003 tobacco sales ban on the purchasing behaviour in smoking and non-smoking adolescents aged 13 through 15 years. In contrast to most other studies, the current study not only explores the effect of the new law on smokers and how they may get tobacco, but also includes non-smokers when studying overall purchasing behaviour.5,9,14,15 The main aim was to establish the effect of the tobacco sales ban on the likelihood of buying tobacco, and the composition of the category of buyers in terms of gender, age and smoking status.9,16,17 The second aim was to determine whether those 13–15-year old adolescents who purchased tobacco after the ban differ in purchasing pattern from those buying tobacco before the sales ban. The two aspects of purchasing included here are the frequency of buying tobacco at commercial outlets, and the distribution of purchases over different types of commercial outlets.5,9,18–21
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Methods |
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Respondents
Two cross-sectional studies were carried out, one before implementation of the tobacco sales ban in 1999 and another 11 months after implementation of the tobacco sales ban in 2003. Telephone interviews lasting 10–15 min were held among samples of adolescents aged 13 through 15 years.17,22 The sampling frame was a large database23 of more than 4 million households for which the age of the adolescents living at home was known. After selecting the households with children aged 13–15 years, random samples of adolescents in these age groups were approached a maximum of five times to participate in a telephone interview. Response rates in 1999 and in 2003 (81% and 83%, respectively) were very similar (table 1). In both survey years the fieldwork took place in November and December. For the 2003 survey this means that the new law had been in effect for 11 to 12 months. It is important to note that the sample was disproportionately stratified with the purpose to interview 400 tobacco-purchasing adolescents in each age category (table 1). This disproportionate sampling means (among other things) that prevalence figures for both buying and smoking cannot be generalized directly to the general population of 13- and 15-year-olds in 1999 and 2003.
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All respondents are used in the analyses of the effect of the new law on the likelihood of purchasing tobacco. In the analysis of changes in purchasing behaviour among buyers, only tobacco buyers are included (1999: n = 983; 2003: n = 1027).
Questionnaire
Age and gender were measured by direct questions. The single question ‘Do you smoke? (Yes/No)’ was used to determine smoking status. Purchasing behaviour was measured with two questions: ‘Do you ever buy tobacco to smoke yourself? (Yes/No)’ and the following question for those who answered ‘No’ was: ‘Do you ever buy tobacco for others? (Yes/No)’. When one of the two questions about purchasing was answered positively, specific questions were asked about the frequency of buying, and the types of outlets where they make their purchases. In 1999 the answers regarding the frequency of buying were reported in terms of the number of times in the past year. In 2003 the answers were reported according to the four categories ‘Never’, ‘Less than once per month’, ‘1–3 times per month’ and ‘Once or more times per week’. To make the answers comparable, we recoded the 1999 answers 0 into ‘never’, 1–11 times into ‘less than once a month’, 12–36 times into ‘1–3 times per month’ and 
37 times into ‘once a week or more often’. The last category is not completely comparable with the ‘once or more times a week’ used in 2003. Closer inspection of the 1999 data showed that on an average only very few respondents (n = 26; 2.6%) gave 37–51 times a year as an answer in 1999. Therefore, the 1999 estimate of the proportion buying once a week might be somewhat overestimated.
The distribution of purchases over types of outlets was calculated by adding up the answers to the four questions about having bought tobacco at the tobacconist, petrol stations, supermarkets, bars and cafeterias. The survey year (before and after the 2003 sales ban) was used as indicator of the sales ban.
Statistical analysis
Adolescents were classified into three groups: those who purchased tobacco for themselves; those who purchased tobacco for others; and those who did not purchase tobacco at all. The chi-square test was used to analyse differences between 1999 and 2003 in the proportion buying tobacco for themselves, others or not buying tobacco. Logistic regression was used to analyse the relation of the tobacco sales ban, smoking status, age and gender with the likelihood of purchasing tobacco. For this analysis purchasing tobacco was dichotomized into purchasing tobacco (for themselves or others), and not purchasing tobacco. The regression was performed backwards whereby all independent variables, as well as all interactions between the independent variables, on the likelihood of buying tobacco were tested for significance (P < 0.05). The chi-square test was used to analyse differences in the frequency of buying at commercial outlets between 1999 and 2003, and the t-test was used to analyse the average distribution of purchases over different types of commercial outlets between 1999 and 2003. All analyses were performed with the statistical program SPSS (version 13).
All respondents (1999: n = 3863; 2003: n = 10 981) were used to analyse the effect of the tobacco sales ban on the proportion of adolescents (<16 years) who buy tobacco, and on the differential effects of this ban according to smoking status, age and gender (table 2).
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Results |
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Description of the sample
Table 2 shows that the percentage buying tobacco decreased from 25.4% in 1999 to 9.4% in 2003; similarly, the percentage saying ‘Yes’ to the question ‘Do you smoke’ decreased from 19.6% to 6.3%. However, due to the disproportionate sampling on 400 purchasers in each age group, the composition of the 1999 and 2003 samples in terms of age and proportion of purchasers is slightly different; this means that the figures in table 2 on decrease in smoking and purchasing cannot be generalized to all 13- to 15-year-olds in the Netherlands. Census data of the National Bureau of Statistics were used to weigh the data for age. It appears that the proportion of purchasers among the 13- and 15-year-olds decreased from 26.3% in 1999 to 10.8% in 2003. The age-weighted proportion of smokers decreased from 20.3% in 1999 to 7.4% in 2003 (P < 0.001).
Among the purchasers, the proportion of smokers increased significantly from 51.3 to 59.4%. Surprisingly, however, in both years a considerable proportion of the purchasers consider themselves to be a non-smoker. If we analyse this for the smokers (data not shown), the proportion of smokers buying tobacco for themselves increased significantly from 66.5% in 1999 to 86.4% in 2003 (P < 0.01). However, this increase in the proportion of smokers buying tobacco should be placed in the context of a sharp decrease in the prevalence of smoking. For the total population the proportion of smokers buying tobacco for themselves in 1999 was 13.5% which decreased to 6.4% in 2003.
Likelihood of purchasing tobacco and the tobacco sales ban, smoking, age and gender
To evaluate the effect of the smoking ban on size and composition of the category of buyers a multivariate logistic regression was done with purchasing behaviour (Yes/No) as dependent variable and survey year, age, gender and smoking status as independent variables. We found a significant interaction effect of implementation of the ban with smoking status (P < 0.001) indicating that the influence of the ban on the likelihood of buying differed for smokers and non-smokers. Table 3 presents the outcomes of analyses for the smokers and the non-smokers showing that, after the ban, smokers were about three times (Odds Ratio [OR] = 2.94) more likely to buy tobacco while non-smokers were far less likely (OR = 0.17) to buy tobacco. Both before and after the ban older smokers were more likely to purchase tobacco. Among the non-smoking buyers the interaction effect of the ban with age indicates that there was no age difference in the likelihood of buying before the ban; after the ban, however, older adolescents were more likely to buy tobacco. Reviewing these results in terms of composition of the category of buyers, it appears that the ban is associated with an increase in the proportion of smokers, and in the proportion of older non-smokers among buyers.
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Changes in purchase patterns of tobacco in commercial outlets
The second aim was to establish changes in purchasing patterns after the tobacco sales ban: i.e. the frequency of buying and the spread of purchases over various commercial outlets. There was a relatively large and systematic difference between smokers and non-smokers buying tobacco once a week or more often (table 4).
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Table 4 shows that, compared with 1999, in 2003 the percentage of smokers buying once a week or more often has increased. For non-smoking adolescents the percentage of buying once a week or more often is also somewhat higher in 2003 (difference not significant). This pattern of non-significant differences in proportion of non-smokers buying at least weekly and a significant increase in proportion of smokers buying at least weekly is also found in each age category (13, 14 and 15 years) separately.
The distribution of purchases over different outlets also increased significantly (P < 0.001) from 1.7 types of outlets in 1999 to 1.9 types in 2003. Among smokers the variety of outlets in which they bought tobacco was significantly higher both in 1999 (2.07 vs. 1.28) and 2003 (2.24 vs. 1.45). However, the differences between smokers and non-smokers were similar in 1999 (0.79) and 2003 (0.79).
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Discussion |
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The present study explored the effect of tobacco sales ban on the number of adolescents who purchase tobacco, on the composition of the category of purchasers in terms of smoking status and age, and on changes in frequency of buying and distribution of purchases over different types of outlets. There was a significant overall decrease from 26.3% to 10.8% in the proportion of 13–15-year old adolescents buying tobacco. Surprisingly, the proportion of adolescents who purchased for others (rather than for themselves) was relatively high both before (48.7%) and after (40.6%) the tobacco sales ban. Furthermore, the ban had a differential effect on the likelihood of buying of both smokers and non-smokers. In 2003, the likelihood of non-smokers purchasing tobacco was much lower than in 1999. However, among smokers the likelihood of buying tobacco was higher in 2003 compared with 1999. The ban seems to have led to an increase in age differences in purchasing tobacco. The outcomes show that, after the ban, older non-smokers were more likely to buy tobacco. However, among smokers, the age differences in buying tobacco were similar before and after the ban. In 2003, the proportion of smokers buying tobacco at least weekly was significantly higher; this difference might be somewhat greater than that shown in table 4, because the 1999 estimate of weekly buying might be slightly overestimated. Among non-smokers there was no increase in the proportion buying at least weekly. Also, in 2003 buyers of tobacco spread their purchases over more commercial outlets than in 1999. In both 1999 and 2003, smokers use more types of outlets to buy their tobacco; however, the difference between smokers and non-smokers in the distribution of purchases over different types of outlets was the same in both years.
Rather the large effect of the sales ban on the proportion of adolescents buying tobacco is probably partly due to how the law was introduced and enforced. Before the start of the ban all tobacco retailers were frequently informed about what was expected from them under the new law, how compliance with the new law would be inspected and what fines to expect when not complying with the new law. The main element of the new law was that all young customers buying tobacco should be asked for identification before selling the tobacco. Inspection data show that, of the total 1347 inspections in 2003 in which young people were present as (potential) customer, in only 2% of the cases were fines given because the seller did not ask for identification.24 Also, those who controlled for compliance could themselves immediately fine the seller, while observing that the retailer had failed to ask for identification. This is known to be more effective in promoting the compliance of sellers than having to report non-compliance to the local police or administration who may then decide to fine the seller.9 The outcomes show that the law was comparatively less effective in discouraging older non-smokers from buying tobacco. This is most likely due to the fact that the obligation of a seller to ask for identification is specified for ‘customers younger than 16 year’. Sellers might more often refrain from asking 15-year-olds for their identification because, in their eyes, they may (already) look like 16-year-olds. From this viewpoint it would probably be more effective to increase the age at which sellers are obliged to ask for identification (e.g. to 18 or 20 years) in order to encourage better compliance.
After the sales ban the increase in the likelihood of smokers to buy tobacco, although not expected, is not the most surprising outcome. Other studies have shown that the introduction of such laws does not always lead to a decrease in the buying behaviour of smokers.5,14 Those who started or continued to smoke after the sales ban are probably comparatively more ‘deviant’ in terms of unlawful behaviour (including buying tobacco) than smokers before the sales ban. However, most surprising was that a large proportion of the buyers of tobacco consider themselves to be a non-smoker, and that the overall decrease in tobacco buying among 13- and 15-year-olds is mainly due to a sharp decrease in the likelihood of buying among non-smokers. As far as we know, no other studies have reported that the main effect of a tobacco sales ban is a decrease in the likelihood of buying among non-smoking adolescents.
Another important point is how to accurately interpret ‘non-smoking’. It is unknown whether those who answered ‘No’ to our question ‘Do you smoke?’ have never smoked, or have stopped smoking, or smoke only very occasionally (e.g. once a month). However, one would expect that if some of the ‘non-smokers’ smoke very infrequently or have stopped smoking in the last year, this group might have answered ‘Yes’ to the question about whether they bought tobacco for themselves. It appears that both in 1999 (0%) and in 2003 (0.5%) none or very few of the non-smokers who reported to buy tobacco indicated to buy it for themselves. Of course this does not exclude that many of the non-smokers who reported to buy for others may occasionally experiment with tobacco themselves. However, it does indicate that the two main ways in which a tobacco sales ban may influence adolescent smoking are: (i) discouraging non-smokers (i.e. experimental and infrequent smokers) to start and from continuing to buy tobacco, and (ii) decreasing the availability of tobacco for more regular smokers, because after the ban non-smokers are far less likely to buy for ‘others’. The decrease in the likelihood of non-smokers buying for others after the ban might be due, for example, to a parent or an older sibling no longer asking the non-smoker to buy cigarettes/tobacco for them; however, it is most likely that non-smokers purchase for their peers. The significant increase in the frequency of buying of smokers after the sales ban supports that smokers have to increase their own efforts to be able to smoke. Another question is the extent to which the ban has changed the sources for tobacco for non-smokers who intend to start smoking. Our study indicates that they are less likely to buy tobacco themselves. However, we do not know the extent to which the decrease in buying tobacco themselves is compensated for by a supply from other sources: for example, by offers from smoking peers, brothers, sisters or parents. Further study is required to specify for non-smokers intending to start smoking to what extent a sales ban is compensated for by additional/different sources of tobacco.
In terms of prevalence, our study indicates a decrease in smoking among adolescents aged 13 through 15 years. This seems to be in line with many western European countries.25 From a health point of view the main question is whether a decrease in tobacco purchase will lead to a lower prevalence of smoking. Two major points need to be discussed before drawing conclusions about the possible contribution of the sales ban to a decrease in smoking prevalence. One point concerns the prevalence of smoking as measured in the present study. It is clear that a prevalence based on the single question (‘Do you smoke?’) is not comparable with prevalence estimates based on a more elaborate and standardized set of questions about smoking.26 The other point concerns our study design; this design does not allow to attribute all changes in smoking prevalence directly to the one (major) event, i.e. the introduction of the sales ban. Other factors possibly influencing young people's smoking may have occurred in the 4-year period covered in this study and should be taken into account when estimating the possible influence of a tobacco sales ban. Concerning the prevalence of smoking, our study shows a strong decrease in smoking among 13- to 15-year-olds from 20.3% in 1999 to 7.4% in 2003 (P < 0.01). Other studies using more elaborate measures to measure smoking only provide estimates for 12- to 18-year-olds3; in this latter age group the decline in the prevalence of smoking at least monthly was 27% in 1999 to 18% in 2003 among boys (P < 0.01) and 27 to 22% among girls (difference not significant). For boys and girls together the prevalence of monthly smoking declined from 27% in 1999 to 20% in 2003 (P < 0.05). There are no indications that the composition of the category of smokers in terms of type of school and ethnic background has changed between 1999 and 2003.3 Another Dutch study using a more elaborate set of questions to measure smoking shows that in 2005 (first time that the whole cohort aged 13–15 years in that year were exposed to the sales ban of 2003), the prevalence of smoking in the last month had further decreased to 17.8%.27 Our study indicates a larger decline in smoking than other studies. However, all studies report a significant decrease in prevalence of smoking between 1999 and 2003, a decrease which continued into 2005.
An important point remains: to what extent did the introduction of the sales ban contribute to the decrease in the prevalence of smoking? Other developments including a period effect on the prevalence of smoking by adolescents in western European countries may have influenced the prevalence of smoking. Some indication of whether the sales ban has contributed to the decrease in prevalence of smoking after 1999 can be acquired by comparing the period 1999–2003 with that of the preceding period (1996–99) in terms of changes in prevalence of smoking and major changes in factors known to influence smoking. Price increases are associated with a decrease in the prevalence of smoking.28–33 The price increase of (on average) 5% per year between 1999 and 2003 is only marginally higher than the 4.5% price increase per year in the period 1996–99.34 The decrease in prevalence of smoking among 12- and 18-year-olds3 was, however, much smaller (difference not significant) between 1996 (29.5%) and 1999 (27%) than between 1999 (27%) and 2003 (20%) (P < 0.05). The further decrease in prevalence between 2003 and 2005 (17.8%) is likely partly due to a higher increase of price in 2004 (26%).34 A higher budget for and more effective methods of health education initiatives to discourage smoking among adolescents may also influence prevalence of smoking. However, there were no major changes in the budget for health education or methods used before and after 1999. Therefore, in our opinion, the 2003 sales ban has contributed to a decrease in buying of tobacco and prevalence of smoking.
Conflicts of interest: None declared.
Key points
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