Table 6.
Results of the regression analyses.
| Outcome/factors | Univariable | Multivariable | ||||
| (n) | Coefficient (95% CI) | P-value | (n) | Coefficient (95% CI) | P-value | |
| Risk-adjusted mortality: | ||||||
| Volumea | 16 | −0.43 (−1.14, 0.28) | 0.22 | 12 | −0.51 (−2.58, 1.57) | 0.57 |
| Ward bedsb | 16 | 0.23 (−0.05, 0.51) | 0.10 | 12 | 0.07 (−0.43, 0.56) | 0.76 |
| Patients per nursec | 9 | −0.17 (−0.45, 0.11) | 0.19 | – | - | – |
| Critical care bedsd | 16 | −0.01 (−0.21, 0.15) | 0.73 | 12 | −0.05 (−0.25, 0.16) | 0.58 |
| Critical care consultantse | 12 | 0.05 (−0.04, 0.14) | 0.24 | – | - | – |
| Critical care traineese | 12 | 0.08 (0.01, 0.15) | 0.038 | 12 | 0.07 (−0.08, 0.21) | 0.31 |
| Research active unitf | 16 | 0.11 (−0.60, 0.81) | 0.75 | 12 | 0.02 (−2.00, 2.04) | 0.98 |
| Resternotomy for bleeding: | ||||||
| Volumea | 14 | 0.56 (−0.76, 1.87) | 0.92 | 12 | 0.56 (−2.26, 3.38) | 0.65 |
| Ward bedsb | 14 | 0.06 (−0.50, 0.63) | 0.81 | 12 | 0.32 (−0.35, 0.99) | 0.29 |
| Patients per nursec | 7 | 0.16 (−0.25, 0.57) | 0.35 | – | - | – |
| Critical care bedsd | 14 | 0.03 (−0.11, 0.17) | 0.64 | 12 | −0.01 (−0.29, 0.26) | 0.92 |
| Critical care consultantse | 11 | −0.05 (−0.24, 0.13) | 0.54 | – | - | - |
| Critical care traineese | 12 | −0.09 (−0.23, 0.04) | 0.15 | 12 | −0.17 (−0.36, 0.03) | 0.084 |
| Research active unitf | 14 | 0.94 (−0.30, 2.18) | 0.12 | 12 | 1.25 (−1.49, 3.99) | 0.31 |
| TIA/CVA: | ||||||
| Volumea | 13 | 0.35 (−0.91, 1.62) | 0.55 | 11 | 1.78 (−0.58, 4.14) | 0.11 |
| Ward bedsb | 13 | 0.47 (0.11, 0.83) | 0.015 | 11 | 0.50 (−0.06, 1.06) | 0.069 |
| Patients per nursec | 7 | 0.14 (−0.26, 0.54) | 0.41 | – | - | – |
| Critical care bedsd | 13 | −0.00 (−0.12, 0.11) | 0.94 | 11 | 0.08 (−0.16, 0.31) | 0.45 |
| Critical care consultantse | 10 | 0.06 (−0.16, 0.28) | 0.56 | – | - | – |
| Critical care traineese | 11 | 0.05 (−0.07, 0.17) | 0.37 | 0.05 (−0.12, 0.21) | 0.48 | |
| Research active unitf | 13 | 0.23 (−0.88, 1.35) | 0.66 | 11 | −0.99 (−3.37, 1.38) | 0.33 |
| Haemofiltration: | ||||||
| Volumea | 14 | −0.07 (−1.89, 1.76) | 0.94 | 12 | 0.89 (−3.65, 5.43) | 0.65 |
| Ward bedsb | 14 | 0.80 (0.24, 1.37) | 0.009 | 12 | 0.99 (−0.09, 2.07) | 0.067 |
| Patients per nursec | 7 | 0.60 (0.36, 0.84) | 0.001 | – | - | – |
| Critical care bedsd | 13 | 0.03 (−0.15, 0.21) | 0.74 | 12 | −0.03 (−0.48, 0.41) | 0.87 |
| Critical care consultantse | 11 | 0.06 (−0.18, 0.31) | 0.58 | – | - | – |
| Critical care traineese | 12 | 0.08 (−0.12, 0.27) | 0.39 | 12 | −0.03 (−0.35, 0.29) | 0.82 |
| Research active unitf | 14 | 0.73 (−1.05, 2.51) | 0.39 | 12 | 0.25 (−4.17, 4.66) | 0.90 |
| IABP use: | ||||||
| Volumea | 14 | −1.32 (−4.12, 1.48) | 0.32 | 12 | −0.85 (−9.03, 7.33) | 0.81 |
| Ward bedsb | 14 | −0.16 (−1.33, 1.00) | 0.77 | 12 | −0.60 (−2.54, 1.35) | 0.48 |
| Patients per nursec | 7 | −0.16 (−1.26, 0.95) | 0.73 | – | – | – |
| Critical care bedsd | 14 | 0.13 (−0.11, 0.37) | 0.26 | 12 | 0.22 (−0.58, 1.02) | 0.53 |
| Critical care consultantse | 11 | −0.10 (−0.48, 0.29) | 0.58 | – | – | – |
| Critical care traineese | 12 | −0.11 (−0.42, 0.19) | 0.43 | 12 | −0.12 (−0.69, 0.44) | 0.61 |
| Research active unitf | 14 | 0.93 (−1.75, 3.62) | 0.46 | 12 | 0.39 (−7.56, 8.33) | 0.12 |
a Per 1000 cases/year.
b Per additional 10 beds/1000 cases/year.
c Per additional patient/nurse.
d Per additional bed/1000 cases/year.
e per additional staff member/1000 cases/year.
f yes vs no,
CI, confidence interval; CVA, cerebrovascular accident; IABP, intra-aortic balloon pump; N, number of units; TIA, transient ischaemic attack.