Table 4.
Average weekly rate of undergoing the operation from wait list for isolated coronary artery bypass surgery in British Columbia 1991–2000 and adjusted rate ratios by registration period
| Registration period | Number of operations | Total wait time, weeks | Crude Rate, per 100 | SE | Hazard ratio | 95% CI* |
| 1991–1992 | 1504 | 23047 | 6.5 | 0.2 | 1.00 | referent |
| 1993–1994 | 1646 | 25480 | 6.5 | 0.2 | 1.00 | 0.93, 1.08 |
| 1995–1996 | 1727 | 34186 | 5.1 | 0.1 | 0.70 | 0.65, 0.76 |
| 1997–1998 | 1613 | 30384 | 5.3 | 0.1 | 0.77 | 0.71, 0.83 |
| 1999–2000 | 1501 | 24029 | 6.2 | 0.2 | 0.94 | 0.88, 1.02 |
| All periods | 7991 | 137126 | 5.8 | 0.1 | - | - |
Abbreviations: SE = standard error; CI = confidence interval
*adjusted for priority group and comorbidity; stratified by age and sex
**0 patients were on the wait list on December 31 2001