Table 5

Predicted probabilities of risk of avoiding revision for patients with different blood Co concentrations 5 and 7 years after initial intervention

Cobalt (µg/l)	Males			Females
Cobalt (µg/l)	Probability	Lower CI	Upper CI	Probability	Lower CI	Upper CI
Probability of avoiding ARMD at 5 years
BHR
2	99.7	99.3	100	99.4	98.6	100
5	99.5	98.8	100	98.9	97.5	100
10	99.1	97.9	100	98.1	95.7	100
ASR
2	99.7	99.3	100	99.4	98.6	100
5	99.5	98.4	100	99.0	97.6	100
10	87.8	92.4	97	83.7	75.8	91.6
Probability of avoiding ARMD at 7 years
BHR
2	99.2	98.1	100	98.2	96	100
5	98.4	96.5	100	96.7	92.6	100
10	97.4	94.1	100	94.2	87.5	100
ASR
2	99.2	98.1	100	98.2	96.0	100
5	98.4	96.5	100	96.7	92.6	100
10	78.2	67.0	91.5	57.3	38.8	75.8

ARMD, adverse reaction to metal debris; ASR, Articular Surface Replacement; BHR, Birmingham Hip Resurfacing.