The choice of one course of action also means forgoing another, technically called opportunity cost or forgone alternative. Whereas the patient or household prioritizes and chooses to maximize satisfaction from scarce resources, health care providers make choices on the basis of priority and efficiency, achieving more with less resources, measured by, for instance, matching cost of health interventions with health outcomes. One of the numerous ways of doing this is through an economic evaluation, or the comparative analysis of alternative courses of action in terms of both their costs and consequences (effects). Such analyses assess the relative desirability of two or more alternative interventions.

The cost-effectiveness of health care interventions, including EMS, must be demonstrated definitively if claims of their public health benefit are to have scientific credibility. Since some experts question the merits of interventions to improve resuscitation care, while others endorse such interventions, we believe that economic evaluations of EMS provide critical information to inform public policy. This chapter discusses conducting economic evaluation of health interventions in the out-of-hospital setting and describes a methodology for determining the cost of an EMS intervention to the community it serves that was developed by the EMS Cost Analysis Project (EM-SCAP), sponsored by the U.S. National Highway Traffic Safety Administration.