 Data analysis: Logistic and binomial regression, and multi-level modelling will be used, and latent growth curve modelling LGCM within the framework of structural equations modelling SEM. Moderating and mediating variables, both time variant e.g., association with alcohol using peers and time-invariant e.g. gender will be modelled. Outcome variables will be modelled using appropriate parametric distributions - Poisson distributions for count data outcomes and binomial distributions for categorical data outcomes. All analyses will be conducted in MPlus v5.2 or Stata. As recommended by Graham imputation of missing data will be done. 