42 C.F.R. § 456.101 – UR plan required for inpatient hospital services.

(a) A State plan must provide that each hospital furnishing inpatient services under the plan has in effect a written UR plan that provides for review of each beneficiary's need for the services that the hospital furnishes him.
(b) Each written hospital UR plan must meet the requirements under §§ 456.101 through 456.145.