Cost benefit analysis in diagnostic radiology: glossary and definitions.

Cost efficiency analyses in clinical radiology require the application of m ethods and techniques that are not yet part of the academic qualifications of the specialists. The procedures used are borrowed from economics, decisi on theory, applied social sciences, epidemiology and statistics. Many expre ssions hail from the angloamerican literature and are presently not yet ger manized unequivocally. This survey is intended to present main terms of cos t efficiency analysis in the english version as well as a german translatio n, to give a clear definition and, if necessary, explanatory notes, and to illustrate their application by means of concrete radiologic examples. The selection of the terms is based on the hierarchical models of health techno loy assessment resp. clinical outcome research by Fryback & Thornbury resp. Maisey & Hutton. In concrete terms, both the differences between benefit, outcomes, and utility and the differences between effectiveness, efficacy a nd efficiency and the differences between direct, indirect, intangible, and marginal costs are explained. True cost efficiency analysis is compared wi th cost effectiveness analysis, cost identification analysis, cost minimiza tion analysis, and cost utility analysis. Applied social sciences are repre sented by the Medical Outcomes Study Short Form-36 and the QALY conception. From decision theory both the analysis of hypothetical alternatives and th e Markov model are taken. Finally, sensitivity analysis and the procedures of combined statistical evaluation of comparable results (meta-analysis) ar e quoted.