Severity of Illness (SOI) in CDI metrics refers to which concept?

• A. A measure of the patient's age and comorbidity burden
• B. A measure of the level of illness severity used with ROM to assess risk
• C. Severity of Illness defines how sick a patient is and is used with ROM to assess risk
• D. A chart type used in reporting

Answer: (C)

Severity of Illness measures how sick a patient is and is used with Risk of Mortality to assess risk. In CDI metrics, SOI comes from a standardized system and places patients into categories of illness severity, which, when paired with ROM, allows meaningful risk adjustment and comparison across different patient populations. This makes the description that SOI defines how sick a patient is and is used with ROM to assess risk the most accurate. The other ideas miss the core purpose: age and comorbidity burden describe a separate concept, and a chart type is not related to SOI.