Assigning a response category (RC) score for the Acute Radiation Syndrome: First, determine the subsyndrome severity score (1,2, 3 or 4) for each of the 4 subsyndromes of the Acute Radiation Syndrome: neurovascular, hematopoietic, cutaneous, and gastrointestinal. Second, determine the RC by noting the highest severity score for any of the 4 subsyndromes. For example, if a patient is assigned the following 4 subsyndrome severity scores: neurovascular 2 (N2), hematopoietic 3 (H3), cutaneous 1 (C1), gastrointestinal 2 (G2). the overall RC assigned to that patient is 3.