Compare and contrast the characteristics of bipolar and major depressive disorder. What would a therapist need to know about the client in order to ensure that he or she was correctly diagnosed?

Both bipolar and major depressive disorders are both mental illnesses. The main characteristic of a bipolar person is that one have alternate periods of happiness and depression. A person suffering a major depressive disorder experiences low mood for at least two weeks. A therapist must be keen in observing the patient to arrive at a correct diagnosis.