Questionable Billing for Medicare Part B Clinical Laboratory Services

HHS – Office of Evaluation and Inspections: 7/8/14


Medicare is the largest payer of clinical laboratory (lab) services in the nation. From 2005 to 2010, Part B Medicare enrollment increased by 10 percent, while spending for lab services increased by 29 percent. In 2010, Medicare payments for all Part B lab services totaled $8.2 billion. We conducted this study to identify questionable billing patterns among Medicare lab services.


We based this study on an analysis of Part B claims for lab services with dates of service in 2010. Labs submit claims for each lab service provided for Medicare beneficiaries. Each claim contains information about the lab provider, the ordering physician, the beneficiary, and the lab service. We developed 13 measures to describe labs’ billing patterns and to identify labs with questionable billing patterns. We calculated and analyzed the distribution of the measures for each lab. We then calculated a statistical threshold for the 13 measures and determined whether a lab’s billing was unusually high for each measure. Additionally, we calculated the total number of claims and total allowed amount associated with certain measures of questionable billing. Read More