Cost-effectiveness analysis for clinicians

The current economic news is bad. Expenditure on health care is under scrutiny in every country and with predictions of another economic crash comes pressure on the funding of health care systems - systems that, according to the World Health Organization http://www.who.int/topics/health_systems/en/ webcite are meant to deliver quality service to all people, when and where they need them.At the same time, new products - pharmaceuticals, diagnostic tests, new technologies - continue to be developed and launched. Health care systems are under pressure to pay for all of the potential hope that these provide, sometimes with good reason, sometimes without. This is where cost-effectiveness analysis comes in.In 1990, Detsky and Naglie [1] published one of the first guides to cost-effectiveness analysis for clinicians. As they described it, cost-effectiveness analyses compare the costs and outcomes for a new intervention with an existing alternative treatment, strategy or intervention. The two questions such analyses aim to answer are: how much does the new intervention cost compared with current practice and is it more effective, and if so, how much more? The results of these analyses are presented as additional cost per additional benefit, that is, additional dollars per unit benefit gained. This is the incremental cost effectiveness ratio (ICER). Benefits can be expressed as different outcomes: as change in a physiological or biological unit of measurement (for example, change in glycated hemoglobin (HbA1c)), difference in lives gained (Life Year Gained, LYG), or differences in quality adjusted life years (QALY). The choice of the outcome depends on what data exist that can be used in the evaluation and whether a mathematical model can be developed that simulates the course of the disease or condition and its effect on the quality of life. Inputs into these models are usually derived from multiple sources, including clinical trials, observational studies and routine datab