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[Case-mix index and length of hospitalization]
V D'Andrea1, A Catania, F M Di Matteo
1Department of Surgical Sciences, Sapienza University of Rome, Italy.
Insights
The Adjusted Clinical Groups (ACG) case-mix system classifies patients by disease patterns for resource use estimation. This patient-focused approach impacts hospitalization duration and hospital resource allocation, particularly for surgical services.
Area of Science:
- Health Services Research
- Medical Informatics
- Public Health
Context:
- The Adjusted Clinical Groups (ACG) system is a patient-focused disease classification method.
- It categorizes patients into groups based on disease patterns to estimate healthcare resource utilization.
- Diseases are classified across five dimensions: duration, severity, diagnostic assessment, etiology, and specialty.
Purpose:
- To explain the ACG case-mix system's methodology for patient classification.
- To highlight how the ACG system captures the impact of disease patterns on resource use.
- To discuss the influence of the ACG system on hospital resource management and surgical activity.
Summary:
- The ACG system assigns patients to one of 93 ACG categories based on their diagnostic group combinations, age, and gender.
- It classifies diseases into 32 diagnostic groups (ADGs) across five clinical dimensions.
- The system is integral to the 'case-mix' repayment model, influencing hospitalization duration and surgical planning.
Impact:
- The case-mix system, driven by ACG, has made surgery central to hospital operations due to its productive potential.
- It emphasizes the importance of hospitalization duration, promoting early patient discharge strategies post-surgery.
- The system stimulates surgical activity by aligning resource allocation with expected specialist surgery levels.
Abstract:
The ACG (Adjusted Clinical Groups) case-mix system is a classification method of diseases of patients, focused on the person. Depending on the pattern of these morbid conditions, the ACG system assigns each patient to a single group (an ACG group), which allows to capture the effects of a group of diseases in estimates of resource use. Diseases are classified into a diagnostic group (ADG) according to 5 clinical dimensions: duration (acute, recurrent or chronic), severity (minor/major vs stable/unstable), diagnostic assessment (symptoms vs diseases), etiology (infectious, traumatic or other), specialty (medical, surgical, obstetric, ...). All diseases can be classified into these dimensions and into one of 32 groups. The ACG case-mix system uses an algorithm to classify each patient into one of 93 ACG categories. Each person is assigned to an ACG according to his ADG combination, his age and his gender. With the repayment system "case-mix", surgery has become central for all great hospitals in virtue of its great productive potential. The case-mix index is one of the factors which influence the duration of hospitalization. The case-mix system has emphasized the importance of the duration of hospitalization, encouraging the planning of programs in order to discharge patients early after surgical operations. It has also stimulated the surgical activity in operating units with "budget" forecasts in which resources are provided according to an expected level of specialist surgery.
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