Sample size calculation and power
The power calculation is based on Hedges et al. [Number the phases is equal to one (i.e., we have one baseline phase and one intervention phase)Intraclass coefficient correlation of 0.5Autoregressive effect 0.5Alpha error probability of 0.016 (giving we have three primary outcomes)Minimum number of observations per phase is threeMinimum detectable effect size is a Cohen’s Under those input parameters, our power is 75.84%; however, it is important to note that our study has an unbalanced design (different amounts of observations per phase resulting in the intervention phase being larger than the baseline). This is designed specifically to improve the adherence of the students and their families on the study. In our experience, being without intervention for more than 6 months (e.g., baseline phase) would reduce the interest and adherence of the participants in the trial. Therefore, our observable power will be superior than the above reported. The estimation of the power was conducted using the Power Analysis and Sample Size software (PASS) [