The Effectiveness of AN-DRGs in Classification of Acute Admitted Patients with Diabetes

The Australian National Diagnosis Related Groups (AN-DRGs) classification is intended to assign acute admitted patient episodes to classes which are iso-resource and clinically homogeneous. It has been widely used to good effect, but its performance has been questioned with respect to the classification of patients with chronic conditions.

The primary aim of this study was to investigate the extent to which AN-DRGs classify episodes of care for a chronic disorder (in this case diabetes) into classes which are relatively homogeneous in terms of clinical attributes and the resources used in the provision of care.

The records of 2094 patients admitted during 1994–95 to four hospitals in the Illawarra Area Health Service with at least one diabetes diagnosis recorded in the discharge summary were reviewed. We found that the source data used for assignment contained errors of medical documentation, abstraction and sequencing, and coding. The sampled patients were distributed among many AN-DRGs in a way which was neither clinically coherent nor obviously descriptive of resource-use differences. The AN-DRG logic appears to ignore or otherwise under-estimate the effects of diabetes as a secondary diagnosis.