Code of Federal Regulations Title 42. Public Health § 42.412.60 DRG classification and weighting factors

(1) The classification of a particular discharge is based, as appropriate, on the patient's age, sex, principal diagnosis (that is, the diagnosis established after study to be chiefly responsible for causing the patient's admission to the hospital), secondary diagnoses, procedures performed, and discharge status.

(2) Each discharge is assigned to only one DRG (related, except as provided in paragraph (c)(3) of this section, to the patient's principal diagnosis) regardless of the number of conditions treated or services furnished during the patient's stay.

(3) When the discharge data submitted by a hospital show a surgical procedure unrelated to a patient's principal diagnosis, the bill is returned to the hospital for validation and reverification. CMS's DRG classification system provides a DRG, and an appropriate weighting factor, for the group of cases for which the unrelated diagnosis and procedure are confirmed.

(1) A hospital has 60 days after the date of the notice of the initial assignment of a discharge to a DRG to request a review of that assignment. The hospital may submit additional information as a part of its request.

(2) The intermediary reviews the hospital's request and any additional information and decides whether a change in the DRG assignment is appropriate. If the intermediary decides that a higher-weighted DRG should be assigned, the case will be reviewed by the appropriate QIO as specified in § 466.71(c)(2) of this chapter.

(3) Following the 60–day period described in paragraph (d)(1) of this section, the hospital may not submit additional information with respect to the DRG assignment or otherwise revise its claim.