Minimum detectable effect size for main outcomes (accounting for sample
design and clustering)
Minimum detectable effect size is minimum difference in Student-Family treatment effects that we can detect given our sample size, number of clusters, a power of 0.8 and the intra-cluster correlation in the specific outcome variable at baseline. The sample allows us to obtain a power of 80%, with a significance level of 5%, a minimum detectable effect size of 0.2 standard deviation, intracluster correlation of 0.27, cluster size of 30 and an R2 of 0.26-0.29.