"Improper payments to fee-for-service Medicare amounted to $10.4 billion in fiscal 2008, decreasing to a rate of 3.6% from 3.9% in 2007, the CMS reported."
FierceHealthcare.com reported that the lower error rate was due to the Medicare Recovery Audit Contractors (RAC).
You can read about the RAC impact on physical therapists here, here, and here.
AIS Health.com reports that the RACs will be delayed a few months (probably February 2009) while some of the government contractors work through a grievance process that is related to selection of RACs, not to health care providers.
As I've previously posted there is evidence to indicate that RACs preferentially targeted large, inpatient hospitals in the 'temporary' 3-year phase.
More restrictive audit rules for the permanent RACs increase the chance that the permanent RACs will continue to target large, institutional providers and leave small ones (eg: physical therapists) alone.