Table 3.
Adjusted mortality rates per 1000 hospital episodes by volume of hospital and surgical team (95% CI)
| Episodes | Teams | Death within 7 days postadmission | Death within 30 days postadmission | Death at hospital | ||||
| Hospital volume (n=10 344) | ||||||||
| Low (<250) | 1450 | 100 | 25.8 | (17.8 to 33.8) | 53.5 | (42.3 to 64.7) | 74.2 | (61.1 to 87.2) |
| Medium (250–449) | 3069 | 187 | 24.9 | (19.3 to 30.4) | 62.5 | (54.1 to 70.9) | 78.4 | (69.2 to 87.6) |
| High (450+) | 5825 | 433 | 27.2 | (23.0 to 31.4) | 55.5 | (49.8 to 61.2) | 75.8 | (69.4 to 82.2) |
| Team volume (n=8958) | ||||||||
| Low (<30) | 1042 | 85 | 30.5 | (20.7 to 40.3) | 62.1 | (48.6 to 75.7) | 84.5 | (69.0 to 100.0) |
| Medium (30–59) | 2775 | 68 | 31.8 | (25.7 to 37.8) | 63.2 | (54.9 to 71.5) | 75.1 | (66.2 to 84.0) |
| High (60+) | 5141 | 54 | 18.8 | (14.9 to 22.7) | 43.0 | (37.4 to 48.6) | 55.0 | (48.8 to 61.1) |
| Teams at low volume hospitals (<250) | ||||||||
| Low (<30) | 103 | 9 | 36.3 | (0.1 to 72.5) | 71.0 | (25.0 to 117.0) | 81.9 | (31.4 to 132.4) |
| Medium (30–59) | 587 | 16 | 24.7 | (12.5 to 36.9) | 47.6 | (30.9 to 64.3) | 60.0 | (41.2 to 78.9) |
| High (60+) | 580 | 8 | 18.8 | (8.0 to 29.7) | 44.4 | (28.2 to 60.6) | 62.2 | (43.4 to 81.1) |
| Teams at medium volume hospitals (250–449) | ||||||||
| Low (<30) | 344 | 25 | 17.5 | (4.6 to 30.3) | 49.6 | (29.2 to 69.9) | 78.0 | (53.1 to 102.9) |
| Medium (30–59) | 906 | 24 | 28.9 | (18.8 to 39.0) | 71.2 | (56.3 to 86.2) | 79.4 | (63.7 to 95.2) |
| High (60+) | 1497 | 19 | 23.4 | (15.5 to 31.3) | 52.6 | (41.1 to 64.2) | 61.7 | (49.5 to 74.0) |
| Teams at high volume hospitals (450+) | ||||||||
| Low (<30) | 595 | 54 | 37.8 | (23.4 to 52.1) | 69.1 | (49.8 to 88.3) | 89.5 | (68.1 to 110.9) |
| Medium (30–59) | 1282 | 39 | 36.6 | (27.3 to 45.9) | 64.4 | (52.4 to 76.4) | 78.4 | (65.6 to 91.3) |
| High (60+) | 3064 | 29 | 16.4 | (11.6 to 21.3) | 37.9 | (30.9 to 44.8) | 50.1 | (42.4 to 57.9) |