LITERATURE REVIEW J Neurosurg Pediatr 21:655–665, 2018 ABBREVIATIONS ACPNF = Accreditation Council for Pediatric Neurosurgery Fellowship; h-index = Hirsch index; ih(5)-index = 5-year institutional Hirsch index; ir(5)-index = revised 5-year institutional h -index; r-index = revised h-index. SUBMITTED October 2, 2017. ACCEPTED January 2, 2018. INCLUDE WHEN CITING Published online March 23, 2018; DOI: 10.3171/2018.1.PEDS17535. Taking the next step in publication productivity analysis in pediatric neurosurgery Ryan P. Lee, MD, 1 Raymond Xu, BS, 2 Pooja Dave, 3 Sonia Ajmera, BS, 2 Jock C. Lillard, BS, 2 David Wallace, BS, 2 Austin Broussard, BS, 2 Mustafa Motiwala, BS, 2 Sebastian Norrdahl, MS, 2 Carissa Howie, 3 Oluwatomi Akinduro, BS, 2 Garrett T. Venable, MD, 4 Nickalus R. Khan, MD, 4 Douglas R. Taylor, MD, 4 Brandy N. Vaughn, RN, 5 and Paul Klimo Jr., MD, MPH 4–6 1 Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; 2 College of Medicine and 4 Department of Neurosurgery, The University of Tennessee Health Science Center, Memphis; 3 Rhodes College, Memphis; 5 Le Bonheur Children’s Hospital, Memphis; and 6 Semmes Murphey, Memphis, Tennessee OBJECTIVE There has been an increasing interest in the quantitative analysis of publishing within the feld of neuro- surgery at the individual, group, and institutional levels. The authors present an updated analysis of accredited pediatric neurosurgery training programs. METHODS All 28 Accreditation Council for Pediatric Neurosurgery Fellowship programs were contacted for the names of pediatric neurosurgeons who were present each year from 2011 through 2015. Faculty names were queried in Scopus for publications and citations during this time period. The 5-year institutional Hirsch index [ih(5)-index] and revised 5-year institutional h-index [ir (5)-index] were calculated to rank programs. Each publication was reviewed to determine author- ship value, tier of research, clinical versus basic science research, subject matter, and whether it was pediatrics-specifc. A unique 3-tier article classifcation system was introduced to stratify clinical articles by quality and complexity, with tier 3 being the lowest tier of publication (e.g., case reports) and tier 1 being the highest (e.g., randomized controlled trials). RESULTS Among 2060 unique publications, 1378 (67%) were pediatrics-specifc. The pediatrics-specifc articles had a mean of 15.2 citations per publication (median 6), whereas the non–pediatrics-specifc articles had a mean of 23.0 citations per publication (median 8; p < 0.0001). For the 46% of papers that had a pediatric neurosurgeon as frst or last author, the mean number of citations per publication was 12.1 (median 5.0) compared with 22.5 (median 8.0) for those in which a pediatric neurosurgeon was a middle author (p < 0.0001). Seventy-nine percent of articles were clinical research and 21% were basic science or translational research; however, basic science and translational articles had a mean of 36.9 citations per publication (median 15) compared with 12.6 for clinical publications (median 5.0; p < 0.0001). Among clinical articles, tier 1 papers had a mean of 15.0 citations per publication (median 8.0), tier 2 papers had a mean of 18.7 (median 8.0), and tier 3 papers had a mean of 7.8 (median 3.0). Neuro-oncology papers received the highest number of citations per publication (mean 25.7). The most common journal was the Journal of Neurosurgery: Pediatrics (20%). MD/ PhD faculty members had signifcantly more citations per publication than MD faculty members (mean 26.7 vs 14.0; p < 0.0001) and also a higher number of publications per author (mean 38.6 vs 20.8). The median ih(5)- and ir (5)-indices per program were 14 (range 5–48) and 10 (range 5.6–37.2), respectively. The mean ir (5)/ih(5)-index ratio was 0.8. The top 5 fellowship programs (in descending order) as ranked by the ih(5)-index corrected for number of faculty members were The Hospital for Sick Children, Toronto; Children’s Hospital of Pittsburgh; University of California, San Francisco Benioff Children’s Hospital; Seattle Children’s Hospital; and St. Louis Children’s Hospital. CONCLUSIONS About two-thirds of publications authored by pediatric neurosurgeons are pediatrics-specifc, although non–pediatrics-specifc articles averaged more citations. Most of the articles authored by pediatric neurosurgeons are clinical, with basic and translational articles averaging more citations. Neurosurgeons with PhD degrees averaged more total publications and more citations per publication. In all, this is the most advanced and informative analysis of publica- tion productivity in pediatric neurosurgery to date. https://thejns.org/doi/abs/10.3171/2018.1.PEDS17535 KEY WORDS bibliometrics; pediatric; neurosurgery; ih(5); ranking J Neurosurg Pediatr Volume 21 • June 2018 655 ©AANS 2018, except where prohibited by US copyright law