Detailed results analysis of false-negative and false-positive cases from four hospitals
| Pressure ulcer | Postoperative pulmonary embolism or deep vein thrombosis | Postoperative sepsis | Ventilator-associated pneumonia | Postoperative wound infection | |
| False negative | 49/117 (41.9%) | 0/28 (0.0%) | 10/32 (31.3%) | 8/29 (27.6%) | 23/110 (20.9%) |
| False positive | 20/646 (3.1%) | 31/735 (4.2%) | 37/731 (5.1%) | 58/734 (7.9%) | 33/653 (5.1%) |
| Over-reporting | 20/20 (100%) | 14/31 (45.2%) | 9/37 (24.3%) | 5/58 (8.6%) | 15/33 (45.4%) |
| Present on admission | 0/20 (0.0%) | 11/31 (35.5%) | 0/37 (0.0%) | 8/58 (13.8%) | 7/33 (21.2%) |
| Stringency criteria | 0/20 (0.0%) | 2/31 (6.4%) | 6/37 (16.2%) | 34/58 (58.6%) | 9/33 (27.3%) |
| International Classification of Disease, 9th revision, Clinical Modification specificity | 0/20 (0.0%) | 4/31 (12.9%) | 21/37 (56.8%) | 11/58 (19.0%) | 2/33 (6.1%) |
| Other* | 0/20 (0.0%) | 0/31 (0.0%) | 1/37 (2.7%) | 0/58 (0.0%) | 0/33 (0.0%) |
↵* Sepsis without a previous recent surgical procedure.