For each service, a payment formula contains three<unk> s, one for physician work, one for practice expense, and one for malpractice expense. On average, the proportion of costs for Medicare are 52%, 44% and 4%, respectively. The three<unk> s for a given service are each multiplied by a unique geographic practice cost index, referred to as the GPCI adjustment. The GPCI adjustment has been implemented to account for differences in wages and overhead costs across regions of the country. The sum of the three geographically weighted<unk>  values is then multiplied by the Medicare conversion factor to obtain a final price. Historically, a private group of 29 (mostly specialist) physicians—the American Medical Association's Specialty Society<unk>  Value Scale Update Committee (RUC)—have largely determined Medicare's<unk>  physician work values.
Relative value unit
Form constant
Equivalent dose
Multiple of the median
Indicative limit value
Absolute threshold
Risk of mortality
Effective dose 