Variables used to calculate the rate of door openings per period
| Variable | Period, mean (range) | ||
|---|---|---|---|
| Preincision | Postincision | Total duration | |
| No. of door openings | 28.7 (10–81) | 42.4 (12–134) | 71.1 (35–176) |
| Duration | 34.1 (16–94) | 77.8 (35–161) | 111.9 (53–220) |
| Door opening/min | 0.84 (0.42–1.76) | 0.54 (0.19–0.89) | 0.64 (0.36–1.05) |