Table 1.

Cup survival: 78.73% cumulative survival for the cup alone

Years since operation	Number at start	Failure	Withdrawn	Number at risk	Effective number at risk	Annual failure rate (%)	Annual success rate (%)	Cumulative survival rate (%)	95% lower bound	95% upper bound
0–1	89	3	0	89	89	0.0337	0.9663	0.9663	0.9055	0.9885
1–2	86	0	2	85	86.95	0.0000	1.0000	0.9663	0.9045	0.9886
2–3	84	1	2	83	85.59	0.0120	0.9880	0.9547	0.8878	0.9825
3–4	81	0	2	80	84.12	0.0000	1.0000	0.9547	0.8870	0.9826
4–5	79	1	0	79	83.05	0.0127	0.9873	0.9426	0.8703	0.9757
5–6	78	0	1	77.5	82.07	0.0000	1.0000	0.9426	0.8697	0.9758
6–7	77	0	3	75.5	81.06	0.0000	1.0000	0.9426	0.8692	0.9759
7–8	74	3	1	73.5	80.03	0.0408	0.9592	0.9041	0.8199	0.9513
8–9	70	2	10	65	78.03	0.0308	0.9692	0.8763	0.7851	0.9321
9–10	58	1	13	51.5	74.20	0.0194	0.9806	0.8593	0.7624	0.9207
10–11	44	1	17	35.5	67.51	0.0282	0.9718	0.8351	0.7290	0.9050
11–12	26	0	5	23.5	58.40	0.0000	1.0000	0.8351	0.7199	0.9089
12–13	21	1	7	17.5	49.50	0.0571	0.9429	0.7873	0.6549	0.8784
13–14	13	0	5	10.5	39.12	0.0000	1.0000	0.7873	0.6366	0.8867
14–15	8	1	4	6	28.60	0.1667	0.8333	0.6561	0.4731	0.8021
15–16	3	0	3	1.5	13.43	0.0000	1.0000	0.6561	0.3947	0.8481