Abstract: A method and system for analyzing historical medical provider billings to statistically establish a normative utilization profile. Comparison of a medical provider's utilization profile with a normative profile is enabled. Based on historical treatment patterns and a fee schedule, an accurate model of the cost of a specific medical episode can be created. Various treatment patterns for a particular diagnosis can be compared by treatment cost and patient outcome to determine the most cost-effective treatment approach. It is also possible to identify those medical providers who provide treatment that does not fall within the statistically established treatment patterns or profiles.

Abstract: In a method of widening the zone of stable operation of an axial-flow fan, and of attenuating noise generated thereby, a portion of the flow medium is drawn off upstream of the fan and is returned to a zone at the periphery of the fan rotor. The invention also includes an axial-flow fan for carrying out the method.