Main effect analyses showed no programme effects on incidences of alcohol consumption ( life-time prevalence : e-learning condition : B = @ , P = @ ; integral condition : B = -@ , P = @ ; @-month prevalence : e-learning condition : B = @ , P = @ ; integral condition : B = -@ , P = @ ) , tobacco consumption ( life-time prevalence : e-learning condition : B = @ , P = @ ; integral condition : B = @ , P = @ ; @-month prevalence : e-learning condition : B = @ , P = @ ; integral condition : B = @ , P = @ ) , or marijuana consumption ( life-time prevalence : e-learning condition : B = @ , P = @ ; integral condition : B = @ , P = @ ) .