<qa>  What percentage of patients are in the outpatient payer mix?The patient population will consist of psychiatric outpatients who meet criteria for the DSM-IV diagnosis of Major Depressive Disorder with Panic Attacks or Panic Disorder. The subjects will be recruited from the Center for Treatment of Affective Disorders and from the Anxiety and Trauma Center in the Department of Psychiatry at the Beth Israel Medical center that provide care to 900 patients. At present, the patient ethnic and racial mix is 50 Hispanic, 15 African American, 32.5 Caucasian and 2.5 Asian. The gender distribution is approximately 33 male and 67 female. The outpatient payer mix is 20 Medicare, 74 Medicaid and 6 combined. Of those patients, approximately 40 360 manifest panic attacks. Based on our previous experience with recruitment for research studies, we expect that 10-12 of patients 36-42 meeting diagnostic criteria will also meet the inclusion and exclusion criteria, will sign the inform consent and will participate in the study. We expect to recruit 40 patients per year and to complete the study in 3 years. 