Economic analyses, which can be either descriptive or evaluative, can help to ensure that healthcare resources are used effectively. Most studies of diabetes mellitus have been descriptive and have used the cost-of-illness methodology, which estimates the burden of a disease to society. This method provides an estimate of the direct, indirect and intangible costs of a disease or illness. ... [Show full abstract] Methodological problems are mainly related to the measurement of indirect costs and even to whether they should be included at all. Existing studies that have measured the direct costs of non-insulin-dependent diabetes mellitus (NIDDM, type II diabetes) serve to highlight the difficulties involved in comparing costs between countries with different healthcare systems, and the importance of defining the study population and the sources of the costs. There is a lack of recent data on the costs of treating people who have diabetes.