[Controversial issues in economic evaluation (I): perspective and costs of Health Care interventions].

Economic evaluation of health care interventions has experienced a strong growth over the past decade and is increasingly present as a support tool in the decisions making process on public funding of health services and pricing in European countries. A necessary element using them is that agents that perform economic evaluations have minimum rules with agreement on methodological aspects. Although there are methodological issues in which there is a high degree of consensus, there are others in which there is no such degree of agreement being closest to the normative field or have experienced significant methodological advances in recent years. In this first article of a series of three, we will discuss on the perspective of analysis and assessment of costs in economic evaluation of health interventions using the technique Metaplan. Finally, research lines are proposed to overcome the identified discrepancies.