Until the 1960-ties, there was considerable debate on whether or not depression exists before adulthood. Next, there were popular concepts, which emphasized that depression during adolescence is "normal" for that particular stage of development. From 1980-ties, adolescent depression is seen as the same problem as with adults. The diagnosis of depression in adolescents is based on adult diagnostic criteria. Today, there is a more generally accepted standard that adolescence depression is essentially the same phenomenon as adult depression but with some development specific modifications. As compared with adults, adolescents with depression demonstrate a more variable course. The adolescent with depression may exhibit somatic complaints, school difficulties and deconcentration rather than depressed mood. Three conceptualizations of depressive phenomena during adolescence have been presented in the literature: (1) depressed mood alone, (2) depressive syndrome, and (3) depressive disorders. Compas, Ey and Grant have compared and integrated different approaches to a synthesis that reflected a comprehensive model of depressive phenomena during adolescence. Depressed mood, syndromes, and disorders are integrated as 3 levels of depressive phenomena in a hierarchical and sequential model.