This article tries to present a broad view on the values and ethicalissues that are at stake in efforts to rationalize health policy on thebasis of economic evaluations (like cost-effectiveness analysis) andrandomly controlled clinical trials. Though such a rationalization isgenerally seen as an objective and `value free' process, moral valuesoften play a hidden role, not only in the production of `evidence', butalso in the way this evidence is used in policy making. For example, thedefinition of effectiveness of medical treatment or (...) health care serviceis heavily dependent on dominant individual or social views about thegoals of the particular treatment or service. There is also a concernthat a reliance on EBM in health policy will occur at the expense ofwidely shared social values like equity and solidarity. Moreover, thereis a concern that when economic considerations and rational proceduresbecome more influential, various `outside' groups third parties likeinsurance companies and policy makers will get a stronger influence onmedical practice which may lead to a change in the patient-providerrelationship. The authors conclude that social values and patientpreference should be explicitly addressed when health policy making isbased on economic and other scientific evidence. (shrink)