Table 1.

Revision rates of Quadra-H/Versafit total conventional hip replacement by operation group (all surgeons)

Number of operations	Number revised	Total number	Observation years	Revisions/100 observation years (95% CI)
1–15 operations	32	635	1872	1.71 (1.17–2.41)
16–30 operations	14	475	1270	1.10 (0.60–1.85)
31–50 operations	20	570	1263	1.58 (0.97–2.44)
51–100 operations	19	981	1678	1.13 (0.68–1.77)
> 100 operations	31	2838	4466	0.69 (0.47–0.99)
Total	116	5499	10550	1.10 (0.91–1.32)

CI = confidence interval.