DIAGNOSTIC INFORMATION AS A COMMODITY

In estimating the cost-effectiveness of diagnostic procedures, it is h elpful to treat diagnostic information as a commodity with a unit pric e. The amount of useful information provided by a test result can be m easured in binary units (bits), and the unit price of the information produced by the test result can be expressed in dollars per bit in muc h the same way that the price of gold is given in dollars per ounce. T his allows comparison of the unit prices of various diagnostic tests, examination of the effect of multiple testing, and calculation of the most cost-effective conditions for screening tests.