The 2003 Index of Hospital Quality

All Patient Refined DRGs
APR-DRG Objectives
The primary objective of the HCFA DRG and AP-DRG patient classification systems
was to relate the type of patients treated to the hospital resources they consumed.
This limited focus on resource intensity does not allow providers to classify patients
into other groups for meaningful analysis. The APR-DRG patient classification
system goes beyond traditional resource intensity measures and was designed with
the ability to address the following needs:
C Compare hospitals across a wide range of resource and outcome measures
C Evaluate differences in inpatient mortality rates
C Implement and support critical pathways
C Identify continuous quality improvement initiatives
C Support internal management and planning systems
C Manage capitated payment arrangements.
To meet these needs, the APR-DRG system classifies patients according to severity
of illness, risk of mortality, and resource intensity. Therefore, in the APR-DRG
classification system a patient is assigned three distinct descriptors: base APR-
DRG, severity of illness subclass, and risk of mortality subclass.
Severity of illness can be defined as the extent of physiologic decompensation or
organ system loss of function experienced by the patient. In contrast, risk of
mortality is defined as the patient’s likelihood of dying.
For analyses such as evaluating resource intensity or patient care outcomes, the
base APR-DRGs in conjunction with the severity of illness subclass is used. For
evaluating patient mortality, the base APR-DRGs in conjunction with the risk of
mortality subclass is used.