[Naikan therapy for prolonged depression: psychological changes and long-term efficacy of intensive Naikan therapy].

Objective: Many studies have shown that a considerable number of patients with prolonged depression are refractory to drug therapy or supportive psychotherapy. A few studies have shown the short-term effectiveness of intensive Naikan therapy for prolonged depression, but the long-term effects have not been reported. For other psychotherapies also, few studies have demonstrated their long-term effectiveness for prolonged depression.