This final rule establishes national coverage and administrative policies for clinical diagnostic laboratory services payable under Medicare Part B to promote Medicare program integrity and national uniformity, and simplify administrative requirements for clinical diagnostic laboratory services. This rule addresses public comments received on the proposed rule that was published March 10, 2000. A Negotiated Rulemaking Committee (the Committee) developed the policies as directed by section 4554(b)(1) of the Balanced Budget Act of 1997 (the BBA).