PMD12 The Paradox of League Tables

Abstract

Allocation of limited health care resources is a problem faced by decision makers. In an effort to ease this burden, the idea has developed that economic efficiency can be compared among interventions by the use of league tables—lists of interventions and their corresponding cost-effectiveness ratios derived from various studies. League tables simplify a huge amount of information into a few numbers postulated to be critical to the decision. Desirable as it may be, this simplicity is not warranted. The very concept is suspect as the ratios listed do not compare the cited intervention to the one of interest. Even when all compare to a common reference intervention, they represent inappropriate average ratios. Methodology and assumptions made in creating the individual economic models vary greatly but are typically ignored in the league table. Even without the questionable methods used in some analyses, real and important differences will always exist among models (e.g., disease variation, purpose of studies, and data availability). Even among studies conducted by the same researchers, relevant differences arise. For example, in one study on prevention of cardiovascular disease the cost estimates included only initial acute care. In another on stroke prevention, also by us, costs included subsequent care for up to 15 years after the initial event. This difference can substantially influence the resulting cost-effectiveness ratios. Both approaches are correct for their purpose, but the difference would be unknown to the decision maker viewing the league table. League tables mislead decision makers into feeling informed without realizing how little is known. These problems cannot be cured by methodological guidelines. Pharmacoeconomic researchers should resist creating league tables and thereby providing both too little and too much information to decision makers.