An observational study of the diagnosis of 300 consecutive new patients in a period of four years led to the main observation of a high percentage of bipolar spectrum diagnosis (4), followed to a new classification of “the bipolar spectrum” (ten sub-types of bipolar spectrum mood).

Inside these sub-types also the temperaments have been inserted, even if they are only sub-clinical aspects of the bipolar spectrum (sub-threshold forms).

With the same method (the diagnostic method was based on an analysis of clinical interviews and personal history of the illness) and with the same aims, others 123 consecutive new patients have been valued for the other subsequential two years; then, all the 423 patients of the six years evaluation have been revalued to put in evidence the presence of their temperaments, emerging from their personal anamnesis.

It appears clear that significantly more patients within the series appear to have a soft bipolar illness than a major unipolar depression; the depressive episodes are now considered as only one phase of bipolar spectrum. Besides, every patient with bipolar spectrum disorder already presented in their personal history of the illness a sub-clinical evidence of one temperament (hyperthymic temper.: 35%; cyclothymic temper.: 49%; depressive temper.: 16%).

The subthreshold presence of the temperaments in the history of the patients with bipolar spectrum disorders allow us to consider this crucial way for early diagnosis of bipolar spectrum mood disorders.