[Clinical criteria in evaluating recovery from depression. Methodologic aspects].

According to recent European epidemiological studies, the lifetime prevalence of major depression ranges between 16 and 20%. Information concerning the natural course of depressive illness remain limited. Longitudinal studies of depressed patients are impeded by the inconsistencies of the labelling of change points in the course of illness (remission, recovery, relapse, recurrence...) and of criteria used to define each of them. Recently, definitions of these terms have been proposed but still need to be clinically validated. Internationally accepted definitions are particularly necessary in order to assess the efficacy of antidepressants at 3 levels: during the acute treatment of an episode, for maintenance treatment (recovery from the complete length of an episode) and for prophylactic treatment (reduction of the risk of future episodes).