<qa>  How many study participants will be drawn from patients admitted to the Massachusetts General Hospital for aSixty study participants for 30 randomized will be drawn from patients admitted to the Massachusetts General Hospital medicalsurgical inpatient units for a traumatic injury that occurred in the prior 3 weeks. Study participants must meet criteria for the A1, A2 and at least one additional category of Acute Stress Disorder symptoms i.e., B, C and or D criteria, as determined by the Acute Stress Disorder Interview upon initial evaluation, to qualify for randomization in a 12 week, double-blind flexible-dose treatment trial of escitalopram 10-40 mgd versus placebo. 