An analysis of publication productivity for 1225 academic neurosurgeons and 99 departments in the United States.

OBJECT

Bibliometrics is defined as the study of statistical and mathematical methods used to quantitatively analyze scientific literature. The application of bibliometrics in neurosurgery is in its infancy. The authors calculate a number of publication productivity measures for almost all academic neurosurgeons and departments within the US.

METHODS

The h-index, g-index, m-quotient, and contemporary h-index (hc-index) were calculated for 1225 academic neurosurgeons in 99 (of 101) programs listed by the Accreditation Council for Graduate Medical Education in January 2013. Three currently available citation databases were used: Google Scholar, Scopus, and Web of Science. Bibliometric profiles were created for each surgeon. Comparisons based on academic rank (that is, chairperson, professor, associate, assistant, and instructor), sex, and subspecialties were performed. Departments were ranked based on the summation of individual faculty h-indices. Calculations were carried out from January to February 2013.

RESULTS

The median h-index, g-index, hc-index, and m-quotient were 11, 20, 8, and 0.62, respectively. All indices demonstrated a positive relationship with increasing academic rank (p < 0.001). The median h-index was 11 for males (n = 1144) and 8 for females (n = 81). The h-index, g-index and hc-index significantly varied by sex (p < 0.001). However, when corrected for academic rank, this difference was no longer significant. There was no difference in the m-quotient by sex. Neurosurgeons with subspecialties in functional/epilepsy, peripheral nerve, radiosurgery, neuro-oncology/skull base, and vascular have the highest median h-indices; general, pediatric, and spine neurosurgeons have the lowest median h-indices. By summing the manually calculated Scopus h-indices of all individuals within a department, the top 5 programs for publication productivity are University of California, San Francisco; Barrow Neurological Institute; Johns Hopkins University; University of Pittsburgh; and University of California, Los Angeles.

CONCLUSIONS

This study represents the most detailed publication analysis of academic neurosurgeons and their programs to date. The results for the metrics presented should be viewed as benchmarks for comparison purposes. It is our hope that organized neurosurgery will adopt and continue to refine bibliometric profiling of individuals and departments.