Comparison of characteristics of included patients and operations, according to time period. Values are means for continuous data and percentages for binary data. Differences between periods are shown along with 95% confidence intervals
| Characteristics | Control period | Intervention period | Difference (95% CI) |
|---|---|---|---|
| Patients | |||
| No of patients | 208 | 217 | |
| Age (years) | 69.6 | 71.0 | 1.4 (–0.5 to 3.3) |
| Women (%) | 50.5 | 56.7 | 6.2 (–3.3 to 15.7) |
| Presence of risk factors (%) | 43.8 | 44.2 | 0.4 (–9.0 to 9.9) |
| Operations | |||
| No of operations | 226 | 222 | |
| Preoperative haemoglobin (g/l) | 131.7 | 137.2 | 5.5 (2.7 to 8.2) |
| Preoperative packed cell volume | 38.9 | 41.0 | 2.1 (1.2 to 2.9) |
| General anaesthesia (%) | 31.6 | 30.2 | –1.4 (–9.9 to 7.2) |
| Total hip replacements (%) | 77.0 | 71.6 | –5.4 (–13.4 to 2.7) |
| Bilateral surgery (%) | 0.9 | 1.8 | 0.9 (–1.2 to 3.1) |
| Duration of surgery (minutes) | 115 | 108 | –7 (–13 to 0) |
| Estimated intraoperative blood loss (ml) | 690 | 688 | –2 (–103 to 98) |
| Postoperative haemoglobin (g/l) | 96.2 | 96.1 | –0.1 (–2.9 to 2.7) |
| Postoperative packed cell volume | 28.0 | 28.5 | 0.5 (–0.4 to 1.3) |