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Accuracy of the aristotle basic complexity score for classifying the mortality and morbidity potential of congenital
Sean M O'Brien1, Jeffrey P Jacobs, David R Clarke
1Duke University Medical Center, Durham, North Carolina, USA. obrie027@mc.duke.edu
Insights
The Aristotle Basic Complexity Score (ABC score) effectively predicts risks in congenital heart surgery. This score helps assess surgical performance and guides quality improvement efforts for better patient outcomes.
Area of Science:
- Cardiovascular Surgery
- Pediatric Cardiology
- Health Services Research
Background:
- The Aristotle Basic Complexity Score (ABC score) was developed by international surgeons for assessing congenital heart surgery performance.
- Its effectiveness relies on accurately classifying procedures by morbidity, mortality, and technical difficulty.
- This study validated the ABC score's predictive ability using multi-institutional data.
Purpose of the Study:
- To evaluate how well the ABC score predicts actual morbidity and mortality in 131 congenital heart surgery procedures.
- To assess the ABC score's utility in quality improvement initiatives for congenital heart surgery.
Main Methods:
- Combined data from the European Association of Cardiothoracic Surgery (EACTS) and Society of Thoracic Surgeons (STS) congenital databases.
- Used the C statistic to measure the ABC score's discrimination for in-hospital mortality and prolonged postoperative length of stay (PLOS > 21 days).
- Identified outlier procedures using logistic regression and exact binomial tests.
Main Results:
- A significant positive correlation was found between the ABC score and observed risks of mortality (C=0.70) and prolonged PLOS (C=0.67).
- Several procedures were identified as outliers for mortality and morbidity.
- The ABC score demonstrated good predictive capability for surgical risk.
Conclusions:
- The ABC score generally distinguishes between low-risk and high-risk congenital heart procedures.
- It is a potentially valuable tool for case-mix adjustment in outcomes analysis.
- Future revisions will incorporate empirical data and large database insights for refinement.
Background:
The Aristotle Basic Complexity Score (ABC score) was derived by consensus of an international surgeon panel to facilitate assessment of surgical performance for quality improvement in congenital heart surgery. The utility of the ABC score depends on its ability to correctly classify procedures according to their potential for morbidity, mortality, and technical difficulty. This collaborative study combined two multiinstitution databases to assess how well the ABC score predicts the actual morbidity and mortality potential of 131 congenital heart surgery procedures.
Methods:
Data from the European Association of Cardiothoracic Surgery (EACTS) congenital database (17,838 operations, 56 centers) and the Society of Thoracic Surgeons (STS) congenital database (18,024 operations, 32 centers) were analyzed. Discrimination of the ABC score for predicting in-hospital mortality and postoperative length of stay (PLOS) of more than 21 days was quantified by the C statistic. Procedure-specific rates of mortality and prolonged PLOS were compared with predictions from a logistic regression model, and an exact binomial test was used to identify procedures that were mortality and morbidity outliers.
Results:
There was a significant positive correlation between the ABC score of a procedure and its observed procedure-specific risk of mortality (C = 0.70) and prolonged PLOS (C = 0.67). Several individual procedures were identifed as mortality and morbidity outliers.
Conclusions:
The ABC score generally discriminates between low-risk and high-risk congenital procedures making it a potentially useful covariate for case-mix adjustment in congenital heart surgery outcomes analysis. Planned revisions of the ABC score will incorporate empirical data and will benefit from the large sample sizes of the STS and EACTS databases.
