NASHVILLE (AP) — After six years in court, Vanderbilt University Medical Center has settled a federal lawsuit for $6.5 million over claims that the hospital overbilled Medicare and Medicaid.

WPLN-FM reports that in the whistleblower lawsuit, former doctors claimed the hospital charged higher rates for attending physicians when medical residents performed services.

It claims the hospital billed for unneeded anesthesia and charged for the same surgeon performing multiple operations simultaneously in different rooms.

Medical center general counsel Michael Regier says the settlement aimed to avoid further costs and distractions from the lawsuit, and the hospital still strongly disputes the claims.

Regier said the plaintiffs and federal government found no evidence of wrongdoing.

New Jersey firm Stone & Magnanini LLP, which filed the lawsuit, commended the requirement of a third-party audit on hospital billing.