A Randomized Controlled Trial of Behavioral Activation and Treatment As Usual in the Acute Treatments of Adults with Major Depressive Disorder

INTERVENTION: Behavior In behavioral activation group, 16 sessions of BA treatment, for the first month every week two sessions 50 minutes and for the second and third months of the treatment, every week one session will be held. Intervention 1: In behavioral activation group, 16 sessions of BA treatment, for the first month every week two sessions 50 minutes and for the second and third months of the treatment, every week one session will be held. Intervention 2: Sertraline 25 mg daily for the first week, 50 mg for the second and third weeks, 75 mg for the fourth and fifth weeks and 100 mg for the sixth week and until the end of the treatment. Sertraline 25 mg daily for the first week, 50 mg for the second and third weeks, 75 mg for the fourth and fifth weeks and 100 mg for the sixth week and until the end of the treatment. Treatment ‐ Drugs CONDITION: Depressive episode Major Depressive Disorder. ; Depressive episode PRIMARY OUTCOME: Treatment of major depressive disorder. Timepoint: Before intervention, in the middle of Intervention (45 days after starting treatment) and after treament ( after 3 months treatment duration).). Method of measurement: In BA, by BDI‐II and In TAU, HRSD is used. SECONDARY OUTCOME: Prevention and relapse of major depressive disorder. Timepoint: One year after termination of the treatment. Method of measurement: In BA, by BDI‐II and In TAU, HRSD is used. INCLUSION CRITERIA: Inclusion criteria : diagnosis of major depression according to the SCID‐I, severity above 19 on the BDI and 13 on the HRSD, age 18‐70, written consent to participate with the study. Exclusion criteria : if they have a life time diagnosis of bipolar disorder, organic brain syndrome, psychosis or mental retardation. Additional exclusion criteria are: substantial and imminent suicide risk; a current (e.g., within the past six months) or primary diagnosis of alcohol or drug abuse or dependence or a positive toxicology screen; a primary diagnosis of panic disorder, obsessive‐compulsive disorder, psychogenic pain disorder, anorexia, or bulimia. In addition, participants who did not respond favorably within the preceeding year to medication will be excluded. Participants who have unstable medical condition and using any medication that would complicate the administration of antidepressant medication (medication in my study), or have a known allergy to medication in th