Incidence of registered adverse outcomes in surgical patients over time
| Variable | OR (99% CI)* |
| Year of discharge (reference=1997, with OR 1.00) | |
| 1998 | 1.05 (0.84 to 1.32) |
| 1999 | 1.29 (1.03 to 1.62) |
| 2000 | 1.21 (0.97 to 1.52) |
| 2001 | 1.05 (0.84 to 1.33) |
| 2002 | 1.13 (0.91 to 1.42) |
| 2003 | 1.34 (1.08 to 1.67) |
| 2004 | 1.54 (1.25 to 1.89) |
| 2005 | 1.71 (1.40 to 2.10) |
| Age (per life-year) | 1.03 (1.03 to 1.03) |
| Gender (female/male) | 0.87 (0.78 to 0.96) |
| ASA class† | |
| ASA class 3-5 | 2.42 (2.16 to 2.72) |
| ASA class missing | 1.51 (1.25 to 1.82) |
| High surgical complexity | 1.82 (1.64 to 2.02) |