International Journal of Technology Assessment in Health Care, 26:3 (2010), 263–271. c  Cambridge University Press 2010 doi:10.1017/S0266462310000358 ASSESSMENTS The cost-effectiveness of the SPHERE intervention for the secondary prevention of coronary heart disease Paddy Gillespie, Eamon O’Shea, Andrew W. Murphy, Mary C. Byrne, Molly Byrne National University of Ireland, Galway Susan M. Smith Trinity College Dublin Molly E. Cupples Queen’s University Belfast for the SPHERE Study Team Objectives: The Secondary Prevention of Heart disEase in geneRal practicE (SPHERE) trial has recently reported. This study examines the cost-effectiveness of the SPHERE intervention in both healthcare systems on the island of Ireland. Methods: Incremental cost-effectiveness analysis. A probabilistic model was developed to combine within-trial and beyond-trial impacts of treatment to estimate the lifetime costs and benefits of two secondary prevention strategies: Intervention - tailored practice and patient care plans; and Control - standardized usual care. Results: The intervention strategy resulted in mean cost savings per patient of €512.77 (95 percent confidence interval [CI], −1086.46–91.98) and an increase in mean quality-adjusted life-years (QALYs) per patient of 0.0051 (95 percent CI, −0.0101–0.0200), when compared with the control strategy. The probability of the intervention being cost-effective was 94 percent if decision makers are willing to pay €45,000 per additional QALY. Andrew W. Murphy, Margaret E. Cupples, and Susan M. Smith conceived the study and together with Molly Byrne and Mary C. Byrne participated in the design of the trial and intervention. Paddy Gillespie and Eamon O’Shea undertook the acquisition and analysis of the health economic data. All authors participated in critical revision of the manuscript, and have seen and approved the final version. This study was funded by the Health Research Board and Irish Heart Foundation. The funders had no part in the design of the study; the collection, analysis, and interpretation of the data; the writing of the report; and the decision to submit the article for publication. We thank the other members of the SPHERE study team, including C. Leathem, A. Houlihan, M. O’Malley, V. Spillane, H. Grealish, and P. Ryan (research nurses); M. Corrigan, M. D’Eath, and J. Wilson (qualitative researchers); and A. Kelly, J. Newell, and M. Donnelly (statistical and policy advisers). We also thank the patients and practitioners who participated in the study. 263