International Comparison of Cost of Illness

Abstract

Many countries are reporting data on health care cost. Explaining differences in costs, however, is a challenging task. National Cost of Illness (COI) studies estimate health care cost from a demographic and epidemiologic perspective. International comparisons of COI might help to explain international differences in health expenditure.

Objective: To assess the international comparability of general COI studies and to examine to what extent and why COI estimates differ.

Methods: Five general COI studies (Australia, Canada, France, Germany and the Netherlands) were studied. COI estimates were classified by health provider using the System of Health Accounts (SHA, OECD). In order to get a more comparable set of COI data we selected provider groups that were fully included in all studies and matched with SHA estimates. The cost of these selected provider groups were then added up and new, adjusted COI figures were calculated. In order to explain differences in cost a number of possible determinants were examined: differences in methods, epidemiological differences, demographic differences and treatment variation

Results: At first COI studies do not seem comparable, but the variation in COI patterns decreased after the provider group selection. In general there appeared a similar COI pattern for these countries, despite their health system differences. All countries face high cost of circulatory disease, mental disorders and diseases of the digestive system. Besides these similarities some significant differences were found too: higher cost of circulatory disease in Germany, relatively high cost of respiratory disease in Australia and high cost of mental disorders in the Netherlands. Comparisons of nursing ans residential care expenditure by disease showed major variation. Epidemiologic explanations of differences were hardly found, whereas demographic differences were influential. Significant treatment variation appeared from the hospital data.

Conclusions: A systematic analysis of COI data from different countries can assist in comparing health expenditure internationally. Furthermore all different dimensions of cost data can inform us on the effects of health system differences for different aspects of health care. However these objectives can only be reached further improvement of the SHA, international use of the SHA in COI studies and a standardized methodology.