title: Five-year institutional bibliometric profiles for 103 US neurosurgical residency programs.
abstract: OBJECTIVE
  Various bibliometric indices based on the citations accumulated by scholarly articles, including the h-index, g-index, e-index, and Google's i10-index, may be used to evaluate academic productivity in neurological surgery. The present article provides a comprehensive assessment of recent academic publishing output from 103 US neurosurgical residency programs and investigates intradepartmental publishing equality among faculty members.
  
  
  METHODS
  Each institution was considered a single entity, with the 5-year academic yield of every neurosurgical faculty member compiled to compute the following indices: ih(5), cumulative h, ig(5), ie(5), and i10(5) (based on publications and citations from 2009 through 2013). Intradepartmental comparison of productivity among faculty members yielded Gini coefficients for publications and citations. National and regional comparisons, institutional rankings, and intradepartmental publishing equality measures are presented.
  
  
  RESULTS
  The median numbers of departmental faculty, total publications and citations, ih(5), summed h, ig(5), ie(5), i10(5), and Gini coefficients for publications and citations were 13, 82, 716, 12, 144, 23, 16, 17, 0.57, and 0.71, respectively. The top 5 most academically productive neurosurgical programs based on ih(5)-index were University of California, San Francisco, University of California, Los Angeles, University of Pittsburgh, Brigham & Women's Hospital, and Johns Hopkins University. The Western US region was most academically productive and displayed greater intradepartmental publishing equality (median ih[5]-index = 18, median Ginipub = 0.56). In all regions, large departments with relative intradepartmental publishing equality tend to be the most academically productive. Multivariable logistic regression analysis identified the ih(5)-index as the only independent predictor of intradepartmental publishing equality (Ginipub ≤ 0.5 [OR 1.20, 95% CI 1.20-1.40, p = 0.03]).
  
  
  CONCLUSIONS
  The ih(5)-index is a novel, simple, and intuitive metric capable of accurately comparing the recent scholarly efforts of neurosurgical programs and accurately predicting intradepartmental publication equality. The ih(5)-index is relatively insensitive to factors such as isolated highly productive and/or no longer academically active senior faculty, which tend to distort other bibliometric indices and mask the accurate identification of currently productive academic environments. Institutional ranking by ih(5)-index may provide information of use to faculty and trainee applicants, research funding institutions, program leaders, and other stakeholders.
authors.affiliation: University of Tennessee Health Science Center and |Departments of 2 Neurosurgery and.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Taylor
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Garrett T
authors.initials: GT
authors.lastname: Venable
authors.affiliation: Departments of 2 Neurosurgery and.|Clinical Pharmacy, University of Tennessee;
authors.forename: G Morgan
authors.initials: GM
authors.lastname: Jones
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Jacob R
authors.initials: JR
authors.lastname: Lepard
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Mallory L
authors.initials: ML
authors.lastname: Roberts
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Nabil
authors.initials: N
authors.lastname: Saleh
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Said K
authors.initials: SK
authors.lastname: Sidiqi
authors.affiliation: University of Tennessee Health Science Center and 
authors.forename: Andrew
authors.initials: A
authors.lastname: Moore
authors.affiliation: Departments of 2 Neurosurgery and.
authors.forename: Nickalus
authors.initials: N
authors.lastname: Khan
authors.affiliation: Department of Neurological Surgery, Oregon Health & Science University, Portland, Oregon.
authors.forename: Nathan R
authors.initials: NR
authors.lastname: Selden
authors.affiliation: Departments of 2 Neurosurgery and.|Semmes-Murphey Neurologic & Spine Institute, Memphis, Tennessee; and.
authors.forename: L Madison
authors.initials: LM
authors.lastname: Michael
authors.affiliation: Departments of 2 Neurosurgery and.|Semmes-Murphey Neurologic & Spine Institute, Memphis, Tennessee; and.
authors.forename: Paul
authors.initials: P
authors.lastname: Klimo
mesh_terms: D015706:Bibliometrics; D004526:Efficiency; D006801:Humans; D007396:Internship and Residency / Q000706:statistics & numerical data*; D009493:Neurosurgery / Q000193:education*; D011642:Publications / Q000706:statistics & numerical data*; D011643:Publishing / Q000706:statistics & numerical data*; D014481:United States
keywords: ACGME = Accreditation Council for Graduate Medical Education; Gini coefficient; United States; bibliometrics; e-index; g-index; h-index; i10-index; institutional; neurosurgery; rank; regional