Rationale, design and conduct of a school-based anti-smoking intervention: the "PEPITES" cluster randomized trial

In France smoking initiation rates amongst 11 to 16 year-olds are worryingly high. Several studies show that early initiation to psycho-active substances is a strong predictor of tobacco addiction. Decreasing the age at which tobacco use starts represents a key challenge for reducing tobacco usage. Implementing an intervention trial using educational workshops based on the Theory of Planned Behavior (TPB) and covering the 4 years of secondary school could be effective.

"PEPITES" is an interventional research, using a cluster randomized design. It will allow assessing the effectiveness of interventions both in reducing the tobacco initiation rate and the regular smoking rate of secondary school pupils. We will also evaluate the process of the implementation of the study and thus will help to the transferability of the intervention. A partnership convention was signed between the JDB Foundation and the National Education authority which designated 6 secondary state schools for the PEPITES trial. The 6 schools were randomly allocated to 3 groups of 2 clusters each: 1 control group, 2 different intervention groups with 2 workshops per year during 4 years; In one of this group the 2 last workshops will be dedicated to measure the loss of taste due to tobacco smoking. In each school, all pupils in year 1 with a signed parental authorization (744 pupils) have been included in the trial. The interventions targets one of the variables of the TPB and the reinforcement of psycho-social competencies. We estimated that we could detect a reduction of increase ≥5.5 and 8% respectively in the 2 principal outcomes (risk α of 5%, and β of 80%).

Carrying out a randomized prevention trial in the school environment raises specific problems which it seems useful to detail for other educational actors who would like to perform a similar study. This discussion concerns the acceptation and cooperation of the National Education partners, the risks of contamination, the information given to parents and pupils and their consent, and the representativeness of the schools involved.

ISRCTN85812512 . Registered 15 May 2018 by BioMed Central. (retrospectively registered).