Cost-effectiveness analysis defines trade-offs between costs, harms, and benefits of alternative treatments and combines them into a single metric, the incremental cost-effectiveness ratio (ICER), that can inform decisions about which interventions to recommend when limited resources are available. Gillian Sanders-Schmidler, PhD, professor of population health sciences and medicine at Duke University, explains the method in terms clinicians can understand. Related Article: Cost-effectiveness Analysis for Clinicians