Abstract
Cost-effectiveness analysis has become the dominant method for economic evaluations of healthcare. Two papers estimating the cost-effectiveness of colorectal cancer screening in Denmark [1] and the UK [2] appear in this issue of Health Economics. In this editorial we discuss two methodological issues in relation to these studies. We first discuss what costs should be included in cost-effectiveness analysis. This is followed by a section about the decision rule of cost-effectiveness analysis. The editorial ends with some concluding remarks.