Calculation of resilience variable
REGRESSION
A hierarchical multiple regression was conducted with school burnout symptoms at T3 (during the pandemic) as dependent variable (Y). We first included school burnout symptoms at T2 (pre-pandemic) as independent control variable (Model 1), and then also included COVID-related stress exposure (Model 2). The residuals of Model 2 (observed minus predicted value) were used in further analyses as resilience variable, based onExplanation of resilience variable. 