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A Comprehensive Evaluation of Statistical Reliability in ACS NSQIP Profiling Models
Kristopher M Huffman1, Mark E Cohen, Clifford Y Ko
1*Division of Research and Optimal Patient Care, American College of Surgeons, Chicago, IL †Department of Surgery, University of California Los Angeles David Geffen School of Medicine, and VA Greater Los Angeles Healthcare System, Los Angeles, CA; and ‡Department of Surgery, Washington University in St. Louis; Center for Health Policy and the Olin Business School at Washington University in St Louis; John Cochran Veterans Affairs Medical Center; and BJC Healthcare, St. Louis, MO.
Statistical reliability for most American College of Surgeons
Area of Science:
- Surgical Quality Improvement
- Health Services Research
- Biostatistics
Background:
- The American College of Surgeons' National Surgical Quality Improvement Program (ACS NSQIP) provides hospital quality assessments.
- The January 2013 Semiannual Report included 137 risk-adjusted profiling models.
Purpose of the Study:
- To evaluate the statistical reliability of hospital profiling models within the ACS NSQIP.
- To determine if these models are suitable for assessing surgical quality and hospital performance.
Main Methods:
- Calculated median reliability for each of the 137 ACS NSQIP models.
- Determined the percentage of hospitals achieving acceptable reliability (≥0.40) for each model.
- Computed average median reliability across models with shared outcomes.
Main Results:
- Median reliability varied significantly across models, ranging from 0.91 to 0.005.
- Reliability generally correlated with larger sample sizes and higher event rates.
- 72% of 'Essentials' models met a median reliability of 0.40+, compared to 29% of 'Procedure-Targeted' models.
- 98% of 'All Cases Morbidity' models achieved acceptable reliability, while 0% of 'Procedure-Targeted Pancreatectomy Mortality' models did.
Conclusions:
- A substantial portion of ACS NSQIP 'Essentials' models demonstrate adequate statistical reliability for assessing surgical quality.
- 'Procedure-Targeted' models show evolving statistical reliability with promising initial results.
- The findings advocate for broader consideration of statistical reliability in professional performance assessments.
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