General population versus disease-specific event rate and cost estimates: potential bias for economic appraisals.
Economic appraisals are increasingly being used for reimbursement decision making. Differences exist in the population data sources used in different studies and these differences may result in errors or biased estimates. A review of the literature suggests that very little has been written on this topic and guidelines and good practice documents are silent on the issue. Using illustrative examples, it was found that the population chosen for event/complication costing did not have a large impact on a cost-effectiveness analysis; however, the choice of population did have a large impact for cost-of-illness (COI) estimation. It was found that not controlling for event/complication rates in a nondiseased population resulted in a 15% inflated COI estimate and using event costs from the general population underestimated COI by 20-32%. Our analysis suggests that using event costs from the general population instead of a diseased population may not have a significant impact on cost-effectiveness estimates; however, COI studies should only use excess event/complication rates and should also only use event costs from populations with the disease.
Goeree
Ron
R
Programs for the Assessment of Technology in Health Research Institute, 25 Main St. W., Suite 2000, Hamilton, ON L8P 1H1, Canada. goereer@mcmaster.ca
O'Reilly
Daria
D
Hopkins
Robert
R
Blackhouse
Gordon
G
Tarride
Jean-Eric
JE
Xie
Feng
F
Lim
Morgan
M
D015982:Bias; D003362:Cost-Benefit Analysis; D048909:Diabetes Complications / Q000175:diagnosis / Q000191:economics* / Q000453:epidemiology / Q000628:therapy*; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000191:economics* / Q000453:epidemiology / Q000628:therapy*; D019317:Evidence-Based Medicine; D017408:Guidelines as Topic; D017048:Health Care Costs; D006801:Humans; D018803:Models, Economic; D015203:Reproducibility of Results; D016896:Treatment Outcome