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Response to two recent BMJ papers on mortality after hip replacement: comparative modelling study

Two BMJ observational studies report increased survival of patients after metal-on-metal resurfacing versus cemented or uncemented total hip replacement.1 2 We considered the potential usefulness of these new estimates for lifetime cost effectiveness models, which necessitate extrapolation beyond observed data.3 Cost effectiveness models have assumed similar mortality irrespective of implanted device.4 5 6

McMinn and colleagues examined men under 55 years who received Birmingham hip resurfacing or cemented or uncemented hip replacements (mean age ~48 years).1 Kendal and …