title: Increased pediatric sub-specialization is associated with decreased surgical complication rates for inpatient pediatric urology procedures.
abstract: BACKGROUND
  Increased case volumes and training are associated with better surgical outcomes. However, the impact of pediatric urology sub-specialization on perioperative complication rates is unknown.
  
  
  OBJECTIVE
  To determine the presence and magnitude of difference in rates of common postoperative complications for elective pediatric urology procedures between specialization levels of urologic surgeons. The Nationwide Inpatient Sample (NIS), a nationally representative administrative database, was used.
  
  
  METHODS
  The NIS (1998-2009) was retrospectively reviewed for pediatric (≤18 years) admissions, using ICD-9-CM codes to identify urologic surgeries and National Surgical Quality Improvement Program (NSQIP) inpatient postoperative complications. Degree of pediatric sub-specialization was calculated using a Pediatric Proportion Index (PPI), defined as the ratio of children to total patients operated on by each provider. The providers were grouped into PPI quartiles: Q1, 0-25% specialization; Q2, 25-50%; Q3, 50-75%; Q4, 75-100%. Weighted multivariate analysis was performed to test for associations between PPI and surgical complications.
  
  
  RESULTS
  A total of 71,479 weighted inpatient admissions were identified. Patient age decreased with increasing specialization: Q1, 7.9 vs Q2, 4.8 vs Q3, 4.8 vs Q4, 4.6 years, P < 0.01). Specialization was not associated with race (P > 0.20), gender (P > 0.50), or comorbidity scores (P = 0.10). Mortality (1.5% vs 0.2% vs 0.3% vs 0.4%, P < 0.01) and complication rates (15.5% vs 11.7% vs 9.6% vs 10.9%, P < 0.0001) both decreased with increasing specialization. Patients treated by more highly specialized surgeons incurred slightly higher costs (Q2, +4%; Q3, +1%; Q4 + 2%) but experienced shorter length of hospital stay (Q2, -5%; Q3, -10%; Q4, -3%) compared with the least specialized providers. A greater proportion of patients treated by Q1 and Q3 specialized urologists had CCS ≥2 than those seen by Q2 or Q4 urologists (12.5% and 12.2%, respectively vs 8.4% and 10.9%, respectively, P = 0.04). Adjusting for confounding effects, increased pediatric specialization was associated with decreased postoperative complications: Q2 OR 0.78, CI 0.58-1.05; Q3 OR 0.60, CI 0.44-0.84; Q4 OR 0.70, CI 0.58-0.84; P < 0.01.
  
  
  CONCLUSIONS
  Providers with proportionally higher volumes of pediatric patients achieved better postoperative outcomes than their less sub-specialized counterparts. This may have arisen from increased exposure to pediatric anatomy and physiology, and greater familiarity with pediatric techniques.
  
  
  CONCLUSIONS
  The NIS admission-based retrospective design did not enable assessment of long-term outcomes, repeated admissions, or to track a particular patient across time. The study was similarly limited in evaluating the effect of pre-surgical referral patterns on patient distributions.
  
  
  CONCLUSIONS
  Increased pediatric sub-specialization among urologists was associated with a decreased risk of mortality and surgical complications in children undergoing inpatient urologic procedures.
authors.affiliation: Division of Urologic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: R
authors.initials: R
authors.lastname: Tejwani
authors.affiliation: Division of Urologic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: H-H S
authors.initials: HS
authors.lastname: Wang
authors.affiliation: Division of Urologic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Young
authors.affiliation: Division of Pediatric Anesthesia, Duke University Medical Center, Durham, NC, USA.
authors.forename: N H
authors.initials: NH
authors.lastname: Greene
authors.affiliation: Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC, USA.
authors.forename: S
authors.initials: S
authors.lastname: Wolf
authors.affiliation: Division of Urologic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Wiener
authors.affiliation: Division of Urologic Surgery, Duke University Medical Center, Durham, NC, USA. Electronic address: jonathan.routh@duke.edu.
authors.forename: J C
authors.initials: JC
authors.lastname: Routh
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008511:Medicine; D010372:Pediatrics; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D013520:Urologic Surgical Procedures
keywords: Pediatric; Postoperative complications; Specialization; Urology