Figure 1. The incidence of shivering compared in the routine thermal care and forced-air warming groups postoperatively. With shivering defined as a score greater than 0 on a four-point scale [13](any shivering), the incidence of shivering was 25% in the routine thermal care group and 2% in the forced-air warming group during the initial postoperative period. With shivering defined as a score greater than 2 (whole-body shivering), the incidence of shivering in the routine thermal care group was 8%; no patient in the forced-air warming group shivered.