points higher than non-daily smokers (95% CI = [0.7, 2.8]). Some gender effects were observed, as the association among females was significantly stronger than the association for males from approximately age 14.5 to 16 and from 21 to 23. Marijuana use was also significantly associated with depressive symptoms from ages 12 to 31 for both genders; again, this association was strongest during adolescence. Among 12-year old females, marijuana users had mean depression scores 4.7 points higher than non-users (95% CI = [3.3, 6.2]); 12-year old male marijuana users reported mean depression scores 1.8 points higher than non-users (95% CI = [0.2, 3.3]). The association among females was significantly stronger than the association among males during ages 12 to 16. In contrast, regular HED was only significantly associated with elevated depressive symptoms during adolescence – this association was not significant after age 19 for males and age 21 for females. During adolescence, regular HED had a stronger association with depressive symptoms than either marijuana use or daily smoking. Among 12-year old females, those with regular HED reported mean depression scores 5.5 points higher than non-users (95% CI = [4.0, 7.1]); 12-year old males with regular HED reported mean depression scores 3.6
