Design of Prospective Cost-Effectiveness Clinical Trials: The Critical Role of the Comparator Group

Abstract

Selection of appropriate comparators is critical for prospective cost-effectiveness clinical studies to be valid and useful. The external validity of such studies is dependent on the comparison of the therapy of interest to its “best” alternative, therefore, the selection of comparator(s) is central to study design. In selecting the “best” alternative, the target audience for the study should be considered. From a societal perspective, the most effective alternative treatment used in clinical practice may be considered “best.” From a payer/provider perspective, the range of current treatment alternatives or “usual care” may be considered “best. ”Depending on the stage of development for a particular drug, the choice of comparators may be limited by practical considerations. Challenges are faced in employing “usual care” as a comparator for both marketed and new therapies. Potential solutions are discussed.