Depressive disorders (DD) in adolescence are often misdiagnosed and under-recognised. A major clinical problem regards the high rate of co-morbidity with other disorders, namely substance abuse. The aim of this study was to assess the discriminative power of the Beck Depression Inventory II (BDI-II) to characterise specific social–demographic variables related to DD in adolescence.

A Portuguese version of the BDI-II and a social–demographic questionnaire were administered to 775 Portuguese adolescents (312 males, 463 females; mean age: 16.9 years); 83 adolescents performed a clinical interview following DSM-IV criteria.

Mean BDI-II Portuguese version (BDI-II-P) total score was 10.31 (standard deviation: 8.4), with females reporting more depressive symptoms than males (P < 0.001). Low academic achievement, sleep disturbances, and alcohol consumption were consistently associated with depressive symptoms for both genders. Higher tobacco consumption was significantly associated with depressive symptoms in females. Familial factors did not appear to be associated with depressive symptoms in males. However, a higher frequency of siblings, having separated parents as well as a more extreme perception of the mother's educational style were consistently associated with depressive symptoms in females.

The BDI-II-P showed discriminative power to characterise social–demographic variables related to DD especially in adolescent females.