Participants and procedure
An initial 813 adolescents were recruited from five schools and assessed at baseline (T1).After dropouts from baseline to the 12-month follow-up (T2; dropout n = 241). a final sample of 572 adolescents ages 12-14 years old ( mean = 13.16 years,SD = 73 ) at T1 was used for this study.The sample comprised boys and girls ( boys n = 252; girls n = 320 ) and it was predominantly british ( 98.6% of sample ).