Cognitive therapy is a treatment process that enables patients to correct false self-beliefs that can lead to negative moods and behaviors. The fundamental assumption is that a thought precedes a mood; therefore, learning to substitute healthy thoughts for negative thoughts will improve a person's mood, self-concept, behavior, and physical state. Studies have shown that cognitive therapy is an effective treatment for depression and is comparable in effectiveness to antidepressants and interpersonal or psychodynamic therapy. The combination of cognitive therapy and antidepressants has been shown to effectively manage severe or chronic depression. Cognitive therapy also has proved beneficial in treating patients who have only a partial response to adequate antidepressant therapy. Good evidence has shown that cognitive therapy reduces relapse rates in patients with depression, and some evidence has shown that cognitive therapy is effective for adolescents with depression.