1. Centers for Medicare & Medicaid Services.Fact Sheet: Two-Midnight Rule. Accessed April 11 2021.https://www.cms.gov/newsroom/fact-sheets/fact-sheet-two-midnight-rule-0
2. BlueCross BlueShield of Rhode Island.Payment Policy Outpaient Observation. Accessed April 11 2021.https://www.bcbsri.com/sites/default/files/polices/Outpatient-Observation.pdf
3. Blue Cross Blue Shield of Illinois.Observation Services Tool for Applying MCG Care Guidelines Clinical Payment and Coding Policy. Accessed April 11 2021.https://www.bcbsil.com/pdf/standards/observation_services_cpcp.pdf
4. Medicare.gov.Inpatient or outpatient hospital status affects your costs. Accessed April 11 2021.https://www.medicare.gov/what-medicare-covers/what-part-a-covers/inpatient-or-outpatient-hospital-status
5. Protocol-Driven Emergency Department Observation Units Offer Savings, Shorter Stays, And Reduced Admissions