ABSTRACT
Introduction Costs are an integral part (i.e., the numerator) of the different types of economic
evaluation methods of health care interventions (see Chapter 9, this volume). Although there exists a conceptual difference between cost-of-illness (COI) studies
and more complete economic evaluations, the problem o f estimating the cost of the medical resources used is common to all. One can say the same about whether one is interested in the costing of preventive measures (i.e., vaccination programs or prophylaxis) or interventional measures such as surgery.
