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The influence of decreasing variable collection burden on hospital-level risk-adjustment
Andrew Hu1, Marie Iwaniuk2, Vanessa Thompson2
1Division of Pediatric Surgery, Department of Surgery, Northwestern University Feinberg School of Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, 633 N. Saint Clair St, 20th Floor, Chicago, IL 60011, USA.
Background:
Risk-adjustment is a key feature of the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (NSQIP-Ped). Risk-adjusted model variables require meticulous collection and periodic assessment. This study presents a method for eliminating superfluous variables using the congenital malformation (CM) predictor variable as an example.
Methods:
This retrospective cohort study used NSQIP-Ped data from January 1st to December 31st, 2019 from 141 hospitals to compare six risk-adjusted mortality and morbidity outcome models with and without CM as a predictor. Model performance was compared using C-index and Hosmer-Lemeshow (HL) statistics. Hospital-level performance was assessed by comparing changes in outlier statuses, adjusted quartile ranks, and overall hospital performance statuses between models with and without CM inclusion. Lastly, Pearson correlation analysis was performed on log-transformed ORs between models.
Results:
Model performance was similar with removal of CM as a predictor. The difference between C-index statistics was minimal (≤ 0.002). Graphical representations of model HL-statistics with and without CM showed considerable overlap and only one model attained significance, indicating minimally decreased performance (P = 0.058 with CM; P = 0.044 without CM). Regarding hospital-level performance, minimal changes in the number and list of hospitals assigned to each outlier status, adjusted quartile rank, and overall hospital performance status were observed when CM was removed. Strong correlation between log-transformed ORs was observed (r ≥ 0.993).
Conclusions:
Removal of CM from NSQIP-Ped has minimal effect on risk-adjusted outcome modelling. Similar efforts may help balance optimal data collection burdens without sacrificing highly valued risk-adjustment in the future.
Level Of Evidence:
Level II prognosis study.
Insights
Removing congenital malformation (CM) predictors from the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (NSQIP-Ped) minimally impacts risk-adjusted outcomes. This simplifies data collection without sacrificing valuable risk adjustment for pediatric surgical quality.
Area of Science:
- Surgical Quality Improvement
- Pediatric Surgery
- Health Services Research
Background:
- Risk-adjustment is crucial for the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (NSQIP-Ped).
- Accurate risk-adjusted model variables require meticulous data collection and regular evaluation.
- This study examines the impact of removing congenital malformation (CM) predictors from NSQIP-Ped models.
Purpose of the Study:
- To evaluate the effect of excluding congenital malformation (CM) predictors on risk-adjusted outcome models within NSQIP-Ped.
- To determine if CM variables are superfluous and can be removed without compromising model performance.
- To assess the implications for data collection burden and risk-adjustment accuracy.
Main Methods:
- Retrospective cohort study utilizing NSQIP-Ped data from 2019 (141 hospitals).
- Compared six risk-adjusted mortality and morbidity models with and without CM predictors.
- Assessed model performance using C-index and Hosmer-Lemeshow (HL) statistics; evaluated hospital-level performance changes and performed correlation analysis on odds ratios (ORs).
Main Results:
- Model performance remained similar after removing CM predictors, with minimal differences in C-index (≤0.002) and HL statistics.
- Hospital-level performance metrics (outlier status, quartile ranks) showed negligible changes.
- Strong correlation (r ≥ 0.993) observed between log-transformed ORs in models with and without CM.
Conclusions:
- Excluding CM predictors from NSQIP-Ped risk-adjusted models has a minimal impact on overall performance.
- Efforts to streamline data collection by removing non-essential variables can be explored without compromising risk-adjustment quality.
- This approach may help balance data collection efficiency with the need for robust risk adjustment in pediatric surgical quality initiatives.
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