1. Description of the initial study population
We detail the principal characteristics of this population which was studied in a published article . In September 2014, the start of the study in the 33 classes of 6th graders in the 6 chosen secondary schools, 790 pupils were contacted and 743 (94%) of them were included in the study. Reasons for non-participation (n=47) were: parental refusal (26 cases), pupil refusal (11 cases) and the absence of the pupil the day that the 1st questionnaire was distributed (10 cases).
Comparison between the 2 groups (Control (C) versus Intervention (I)) concerning the general characteristics of the 6th graders only showed (Table 1), among the variables being studied, two significant differences - pupils from the control group more often live in a DUZ and have more non-sporting extracurricular activities (cultural or other) than those in the intervention group.
More than a third of pupils have either their father or mother who are smokers and more than 30% of them are in contact with tobacco at home, of which 12% every day. Pupils in group I are a little more exposed to tobacco smokers at home than those in group C (40.1% vs. 32.8%, p=0.057).
The 6th graders who declared that they had already experimented with tobacco were 10.5% in group C and 11.9% in group I (p=0.58). We noted 45 experimenters of the hookah, of which 37 boys and 8 girls and 61 experimenters of cigarettes, of which 23 girls and 38 boys, with no difference between control and intervention groups. 2.4% of cases declared that they were smokers (0.7% every day and 1.7% occasional), with no difference between groups I and C.
2. Process evaluation
2.1. Carrying out the planned workshops
This study was made possible by private financing for the most part, which allowed us to propose ‘turnkey’ interventions which were free of charge to the schools.
In order to implement a randomized tobacco prevention trial in the school environment, it was necessary, first of all, to convince the academic management of the National Education ministry of the interest of such a methodology (randomization in 2 groups: intervention and control) leading to an « evidence based » evaluation and possible transferability to other schools. The partnership with Paris-Saclay university strengthened the quality of this study.
In order to address the disappointment of the randomized ‘control’ schools and to reinforce the importance of their passive participation in the study, the JDB Foundation had to offer, the first year, a pedagogic program dealing with physical activity whilst not interfering a priori with the study’s objective.
Identifying a contact person for each school (often the school nurse as we are dealing with health issues) greatly helped us conduct the PEPITES study, despite frequent professional transfers (annual turn-over within the teaching staff in the 6 schools over the four year period). Additionally, within the scope of the Education Committee for Health and Citizenship (ECHC) lead by the headmaster and the school nurse, a significant amount of time was dedicated to tobacco prevention debates, which clearly made it easier to carry out the PEPITES study in the schools.
The interventions took place during normal school hours; this « intrusion » might have been viewed by the teachers as extra work and especially as a loss of time with regard to completing the curriculum for the year. In order to get the highest possible rate of participation, it was necessary to spend 16 extra ‘catch-up’ hours, on top of the 354 planned intervention hours over the 4 year period, to collect the data from pupils who were absent from the planned sessions. At the same time the teaching staff also had to organize activities for the 47 pupils who were not included at the start of the study.
In addition to the involvement of the teaching staff, it was also necessary to get the parents and pupils involved throughout the duration of the study. In order for nearly 100% of parents and pupils to agree to participate, they must clearly understand the objective of the study. Pupils must be reassured that their answers will not be shared with either their teachers or their parents, by clearly explaining the system of anonymous answers; this point was especially important as the questions concerned activities that, in principle, were banned.
The pupils liked the fact that we used digital tablets for the answers to the questionnaires and this was a fun and very useful tool for collecting personal data with a low risk of copying. This method was made possible thanks to the Essonne department council providing the tablets for all Essonne schools.
Planning of actions in advance allowed us to establish good relationships with the school staff and this was essential for the JDB Foundation team throughout the study. These relations were maintained through regular contact and annual meetings covering how the study was progressing. In this way we were able to follow the progress of programmed activities despite a wide variety of unforeseen problems (reserved rooms not available, pupils absent, teachers not informed, last minute timetable changes, unstable IT network, national strikes, terrorist attacks…). The individual needs and environment of each school were taken into account as far as possible: on the one hand a certain flexibility regarding logistical organization and planning of educational sessions, and on the other continued support throughout the PEPITES study between the schools and the project leader.
In total, this strict monitoring meant that, of the 8 interventions planned over the 4 years, 70% of pupils took part in 7 or 8 planned workshops, 13% in 5 or 6 and 17% only in half or less. However, regarding data collection, we were unable to prevent a drop-out rate of 33 % by the end of 9th grade.
Table 2 shows the split of drop-outs over time in each of the 2 groups.
Pupil movements over time in each school cannot be controlled and the number of drop-outs is high (33 %) and aleatory variations over time in the 2 groups. Overall the drop-outs are significantly more often boys, living more often in a DUZ, and in a single parent home. They have also more often experienced a traumatic event (divorce, death, illness). Additionally and significantly they like school a lot less, have more contact with tobacco at home and have more friends who experiment with various products; finally, they have a more positive opinion regarding tobacco. Also they experiment significantly more with cigarettes and/or the hookah.
In order to evaluate the impact of the missing data on the overall results, sensitivity analyses were performed, on the one hand on pupils who had not dropped out at the end of 9th grade (n=497), and on the other on pupils who had participated in the 5 evaluations (n=470). The results described later on are similar whichever sample is chosen.
3. Factors influencing experimentation and tobacco smoking
We note that: being a boy, living in a DUZ, not liking school and feeling insecure there, having experienced a traumatic event, not living with your two parents, living with smokers, having daily contact with tobacco smoke, having friends who smoke and having a positive opinion of tobacco – all these factors increase the risk of experimenting with tobacco smoking, either cigarette, cigar, or hookah…
Nevertheless, over time we note a reduction in the gap between girls and boys from the 8th grade onward. Equally living with a single parent becomes less important with time. We observe that the feeling of insecurity at school and the fact of not liking school vary from one year to the next. The other factors remain more constant.
With regard to confirmed smokers, the low number of smokers does not allow us to analyze all these factors. Significant factors are mainly masculine sex, perceived insecurity at school, daily contact with tobacco smoke, and having a positive opinion of tobacco. These factors vary over time as those linked to experimentation.
4. Comparison of the principal outcomes over time in the 2 groups I/C
Overall, with time, and regardless of which type of experimentation, we note in each of the two groups a significant increase in the number of experimenters of tobacco from the start of grade 6 and right up to the end of grade 9: from 10.5 to 44.4% for the control group and from 11.9 to 34.3% for the intervention group. The progression in the number of experimenters is slower in the intervention group compared with the control group. The difference between the two groups during this period becomes significant (p=0.03) only at the end of 9th grade (Figure 1). The adjustment for risk factors linked to tobacco experimentation does not change the results (Table 3).
We also analyzed the number of experimenters over time according to the number of educational sessions attended (< 6 versus ≥ 6) by pupils of the intervention group who were not experimenters at the start of the 6th grade (Figure 2). The effect of the number of sessions is not significant, perhaps due to a weak statistical power, but there is however a tendency in favor of pupils who attended 80% of the sessions.
Concerning the different types of experimentation with tobacco (Table 3) (cigarette, hookah, cannabis, taken on its own or not), the tendency is the same but only significant at the end of grade 9 when taken with cannabis (14.8% of experimenters in the control group, compared to 8.4% in the Intervention group (p=0.03). For those who are « poly-experimenters » (experimenters of at least two products) , we observe at the end of 9th grade rates of 22.2% in the control group and of 15.8% in the intervention group (p= 0.08).
5. Cigarette smokers (Table 4)
Overall the low number of smokers lessens the statistical power of the analysis, and only the cigarette smokers could be analyzed properly.
As with tobacco experimentation, the number of cigarette smokers increases significantly between the start and the end of the study, in both the Control group (from 2.2% to 6.2%) and in the Intervention group (from 2.5% to 3.9%). Concerning daily smokers, their number rises in the C group (0.9% to 3.7%) but remains stable in the I group (0.6%).