“…Severity was defined as mild, moderate and severe. The factors that were used for determining severity were (1) serum albumin value (less than 2.5 g/dl), (2) SpO 2 less than 90% or PaO 2 less than 60 Torr, (3) impaired oral administration of drugs, (4) expansion of newer infiltration shadow on chest X-ray film that was more than half of the lung field, (5) the existence of severe complications such as malignancies, cerebral vascular disorders, hepatic diseases, kidney diseases or heart failure, and (6) administration of corticosteroids. Mild severity was defined as the patient possessing none of the above factors.…”