Two-Midnight Rule Delay Act of 2013

Two-Midnight Rule Delay Act of 2013 - Prohibits the Secretary of Health and Human Services (HHS) from enforcing the two-midnight rule to a hospital for which payment is made under title XVIII (Medicare) of the Social Security Act for admissions occurring before October 1, 2014.

(The two-midnight rule allows Medicare coverage of only hospital stays for which a physician admits to a hospital a beneficiary expected to require care that crosses two midnights, but generally denies coverage of care expected to require less than a two-midnight stay.)

Applies such prohibition to Medicare review contracts.

Prohibits Medicare review contractors from denying a claim for inpartient hospital services furnished by a hospital, or inpatient critical access hospital services furnished by a critical access hospital, for discharges occurring before October 1, 2014: (1) for medical necessity due to the length of an inpatient stay in such hospital or due to a determination that the services could have been provided on an outpatient basis; or (2) for requirements for orders, certifications, or recertifications, and associated documentation relating to such matters.

Prohibits the Secretary from increasing the sample of claims selected for prepayment review under the Medicare Probe and Educate program above the number and type established by the Secretary as of November 4, 2013.

Directs the Secretary to develop: (1) a Medicare hospital payment methodology for short inpatient hospital stays; (2) general equivalency maps to link the relevant International Statistical Classification of Diseases and Related Health Problems (ICD)-10 codes (used to report medical diagnoses and inpatient procedures) to relevant Current Procedural Terminology (CPT) codes, and the relevant CPT codes to relevant ICD-10 codes, in order to permit comparison of inpatient hospital services and hospital outpatient department servives; and (3) a second crosswalk between Diagnosis-Related Group (DRG) codes for inpatient hospital services and Ambulatory Payment Class codes for outpatient hospital services.