Cost-utility Analysis Value-based Medicine Analysis: Ophthalmic Cost-utility Analyses

Melissa M. Brown, MD, MN, MBA Gary C. Brown, MD, MBA Peter Kertes, MD It is the philosophy of Evidence-Based Ophthalmology that the best evidencebased medicine should provide the foundation for knowledge, which will allow practitioners to provide the highest quality of medicine for our patients. Although the knowledge of a numerical or statistical change is critical, this information must be taken to another level to ascertain the true value of evidencebased discoveries to patients and society. As an example, it was shown in the Branch Retinal Vein Occlusion Study that laser treatment of macular edema occurring secondary to retinal vein obstruction yields a long-term mean visual acuity of 20/40-20/50, as compared with a mean visual acuity of 20/70 in the untreated group. But equally as important is the question, ‘‘What does this mean for the quality of life for my patient?’’ Value from an interventional therapy occurs when it positively affects: (1) quality of life and/or (2) length of life. Therapies that do not accomplish at least one of these goals have a questionable role in the armamentarium in the fight against disease. The length-of-life component can often be extracted from evidence-based medical information in the literature. Quality-of-life information, however, is not so readily available. Why? Because many mechanisms for measuring quality have been nonstandardized, inapplicable across diverse medical specialties, and far from uniformly accepted. In 1968, Klarman and associates first used the quality-adjusted life-year (QALY). The QALY measures the value conferred by an intervention. In 1977, Weinstein and Stasson reported a methodology for ascertaining the costeffectiveness of interventional medical therapies. On the basis of utility theory, it has been modified to incorporate: (1) evidence-based medicine, (2) patientbased preferences, (3) decision analysis, and (4) economic modeling with discounting to account for the time value of money. A brief explanation of each of these components follows below: