Table 2 Guarantee of anonymity

The self-assessment questionnaire contains a code which allows the answers from the same pupil to be followed from year to year. This numbered code was randomly generated and assigned to each pupil in the trial. The code is recorded in a list with the pupils’ names which is held by the headmaster of the school in his role as a reliable third party: the headmaster does not have access to the pupils’ answers; the JDB Foundation team which performs the analysis does not have access to the list of pupils’ names. Each time a new questionnaire is completed the code is again supplied to the pupil thanks to the paper list held by the headmaster of the school. This information is also included in the information letter to parents and pupils before completion. The procedures put in place have met that the National Commission for Data Protection and Liberties (CNIL -France) requirements and has authorized the implementation of the PEPITES trial.