The graphs show the percentage distribution of 2022 volumes that are delivered as inpatient versus outpatient cases. Note that globally, “outpatient” encompasses not only hospital-based outpatient care, but also ambulatory and day case volumes. The underlying aggregate volume data comes from two sources^*:

• United States data is sourced from Optum’s de-identified Clinformatics® Data Mart (2007–2022), which is derived from a database of administrative health claims for members of large commercial and Medicare Advantage health plans.
• Non-U.S. data is sourced from The Organisation for Economic Co-operation and Development’s (OECD) Surgical Procedures data explorer tool, which collates ICD volume data from OECD nations to compare surgical procedure location and frequency.