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"July Effect" in Spinal Fusions: A Coarsened Exact-Matched Analysis
Austin J Borja1, Hasan S Ahmad1, Samuel B Tomlinson1
1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Neurosurgery
|January 26, 2023
Summary
The July Effect did not impact outcomes for elective spinal fusion surgery. Patient safety remained consistent throughout the academic year, even with new resident physicians starting in July.
Area of Science:
- Neurosurgery
- Spinal Surgery
- Patient Safety
Background:
- The "July Effect" in healthcare refers to potential declines in patient care quality at the start of the academic year.
- Few studies have investigated this phenomenon in elective spinal procedures.
- Existing research often lacks rigorous methods to control for confounding factors.
Purpose of the Study:
- To investigate the presence of the July Effect in single-level spinal fusions.
- To utilize a coarsened exact matching protocol to control for patient characteristics influencing outcomes.
- To compare surgical outcomes between July and non-July surgeries.
Main Methods:
- Retrospective analysis of 2,338 adult patients undergoing single-level, posterior-only lumbar fusion.
- Primary outcomes included 30-day readmissions, emergency department visits, reoperations, complications, and mortality.
- Coarsened exact matching was applied to create comparable cohorts for analysis.
Main Results:
- No association was found between the operative month and adverse postoperative events within 30 days.
- Patients undergoing surgery in July showed no significant difference in adverse outcomes compared to other months.
- Even after exact matching, July surgeries demonstrated non-inferior adverse event rates.
Conclusions:
- This study found no evidence of a July Effect in single-level spinal fusions.
- The findings suggest that teaching hospitals maintain adequate patient care standards throughout the academic year.
- Patient outcomes are not negatively impacted by the transition of resident physicians in July.
