The EOS 2D/3D X-ray imaging system:a cost-effectiveness analysis quantifying the health benefits from reduced radiation exposure

OBJECTIVES: To evaluate the cost-effectiveness of the EOS® 2D/3D X-ray imaging system compared with standard X-ray for the diagnosis and monitoring of orthopaedic conditions. MATERIALS AND METHODS: A decision analytic model was developed to quantify the long-term costs and health outcomes, expressed as quality-adjusted life years (QALYs) from the UK health service perspective. Input parameters were obtained from medical literature, previously developed cancer models and expert advice. Threshold analysis was used to quantify the additional health benefits required, over and above those associated with radiation-induced cancers, for EOS® to be considered cost-effective. RESULTS: Standard X-ray is associated with a maximum health loss of 0.001 QALYs, approximately 0.4 of a day in full health, while the loss with EOS® is a maximum of 0.00015 QALYs, or 0.05 of a day in full health. On a per patient basis, EOS® is more expensive than standard X-ray by between £10.66 and £224.74 depending on the assumptions employed. The results suggest that EOS® is not cost-effective for any indication. Health benefits over and above those obtained from lower radiation would need to double for EOS to be considered cost-effective. CONCLUSION: No evidence currently exists on whether there are health benefits associated with imaging improvements from the use of EOS®. The health benefits from radiation dose reductions are very small. Unless EOS® can generate additional health benefits as a consequence of the nature and quality of the image, comparative patient throughput with X-ray will be the major determinant of cost-effectiveness.