Table 1 Details of the instrument to be applied among the students at the evaluation time points
Variable | Main Use * | Source | Scale |
|---|---|---|---|
Drug use in lifetime (first use, incidence and prevalence), past year and past month (prevalence) | Primary outcomes (alcohol, tobacco, marijuana, inhalant, cocaine, crack and amphetamine use and binge drinking) | CEBRID [28] | 22 dichotomous questions |
Socioeconomic class | Confounder | ABEP [35] | A scale with 15 items |
Demographic data | Confounders | CEBRID [28] | 2 questions (age and sex) |
Decision-making | Mediator | EUDAP [26] | A scale with 9 dichotomous items |
Positive and negative beliefs | Mediator | Two scales with 11 dichotomous items each (one for alcohol and one for marijuana) | |
Normative beliefs | Mediator | Two scales: a Likert scale with 4 items and a dichotomous scale with 11 items | |
Knowledge about drugs | Mediator | A scale with six items | |
Refusal skill | Mediator | A scale with three items | |
School violence | Secondary outcome | Olweus Bully Victim Questionnaire [30] | Two scales: a scale to measure violence perpetrated with eight dichotomous items each and a scale to measure violence suffered with seven dichotomous items each |
Psychiatric symptoms | Secondary outcome | Strengths and Difficulties Questionnaire [31] | A scale with 25 dichotomous items |
Eating disorders | Secondary outcome | SCOFF [33] | A scale with 5 dichotomous items |