OBJECTIVE Publication has become a major criterion of success in the competitive academic environment of neurosurgery. This is the first study that has used departmental h index-and e index-based matrices to assess the academic output of neuroendovascular, neurointerventional, and interventional radiology fellowship programs across the continental US. METHODS Fellowship program listings were identified from academic and organization websites. Details for 37 programs were available. Bibliometric data for these programs were gathered from the Thomson Reuters Web of Science database. Citations for each publication from the fellowship's parent department were screened, and the h and e indices were calculated from non-open-surgical, central nervous system vascular publications. Variables including "high-productivity" centers, fellowship-comprehensive stroke center affiliation, fellowship accreditation status, neuroendovascular h index, e index ( h index supplement), h10 index (publications during the last 10 years), and departmental faculty-based h indices were created and analyzed. RESULTS A positive correlation was seen between the neuroendovascular fellowship h index and corresponding h10 index (R = 0.885; p < 0.0001). The mean, median, and highest faculty-based h indices exhibited positive correlations with the neuroendovascular fellowship h index (R = 0.662, p < 0.0001; R = 0.617, p < 0.0001; and R = 0.649, p < 0.0001, respectively). There was no significant difference (p = 0.824) in the median values for the fellowship h index based on comprehensive stroke center affiliation (30 of 37 programs had such affiliations) or accreditation (18 of 37 programs had accreditation) (p = 0.223). Based on the quartile analysis of the fellowship h index, 10 of 37 departments had an neuroendovascular h index of ≥ 54 ("high-productivity" centers); these centers had significantly more faculty (p = 0.013) and a significantly higher mean faculty h index (p = 0.0001). CONCLUSIONS The departmental h index and analysis of its publication topics can be used to calculate the h index of an associated subspecialty. The analysis was focused on the neuroendovascular specialty, and this methodology can be extended to other neurosurgical subspecialties. Individual faculty research interest is directly reflected in the research productivity of a department. High-productivity centers had significantly more faculty with significantly higher individual h indices. The current systems for neuroendovascular fellowship program accreditation do not have a meaningful impact on academic productivity.
Keywords: ACGME = Accreditation Council for Graduate Medical Education; CAST = Committee on Advanced Subspecialty Training; DNV = Det Norske Veritas; JC = Joint Commission; UCLA = University of California, Los Angeles; UCSF = University of California, San Francisco; bibliometrics; cerebrovascular; citation analysis; e index; endovascular neurosurgery; endovascular surgical neuroradiology; fellowship program; h index; h index-dept = departmental h index; h index-neuroendovascular = h index for the neuroendovascular fellowship; h10 index = h index for publications in the last 10 years; interventional neuroradiology; neuroendovascular surgery; neurointerventional; neurosurgery department; stroke; subspecialty.