Final answer:
The three-day DRG window rule implies that diagnostic services and related non-diagnostic services provided to a Medicare patient within 3 days preceding an inpatient hospital admission are bundled into the DRG payment. If admitted on Friday, services from the previous Tuesday through Thursday are included.
Step-by-step explanation:
The term three-day DRG window rule, also known as the 72-hour rule, refers to a Medicare cost-saving policy. Under this rule, all diagnostic services and related non-diagnostic services furnished to a Medicare patient during the 3-day period preceding an inpatient hospital admission are considered to be part of the inpatient stay for billing purposes. If a Medicare patient is admitted on a Friday, any laboratory tests, X-rays, CT scans, MRI, and non-diagnostic services such as physical therapy related to the admission diagnosis provided on the preceding Tuesday, Wednesday, and Thursday fall within this window and are bundled into the Diagnosis-Related Group (DRG) payment to the hospital.