In a report entitled “Questionable Billing for Medicare Independent Diagnostic Testing Facility Services,” the OIG discusses its examination of geographic patterns in Medicare independent diagnostic testing facility (IDTF) billing, in which it reviewed 2009 claims by Core Based Statistical Area (CBSA). According to the OIG, 20 high-utilization CBSAs with 2.2% of the total beneficiary population accounted for 10.5% of Medicare Part B payments for IDTF services, and 9% of IDTFs in high-utilization CBSAs provided 90.1% of IDTF services. Additionally, high-utilization CBSAs had twice as many claims with at least two of what OIG characterizes as questionable characteristics as all other CBSAs (e.g., claims involving a beneficiary linked to four or more IDTFs, claims for which beneficiaries did not see their referring physicians within 90 days before or after receiving the IDTF service, or IDTF claims on which the diagnosis category is not the same as the diagnosis category on any other corresponding provider claim for that beneficiary). In response to these finding, the OIG recommends that CMS: (1) monitor IDTF claims for questionable characteristics, (2) take appropriate action when IDTFs submit a high number of questionable claims, and (3) assess whether to impose a temporary moratorium on new IDTF enrollments in CBSAs with high concentrations of IDTFs. CMS concurred with the OIG’s recommendations.