Bibliometric Analysis and Applications of a Modified H-Index Examining the Research Productivity of Neurosurgery Faculty at High-Ranking Academic Institutions

OBJECTIVE: A major critique of the h-index is that it may be inflated by noncritical authorship. We propose a modified h-index (hm), incorporating critical authorship, complementary to the h-index. We analyze its relationship to the traditional h-index, and how each varies across professional categories relevant to academic neurosurgery. This analysis is not meant to critique authorship decisions, affect career development, alter academic legacy, or imply that the concepts of team science or midlevel authorship contributions are not valuable. - METHODS: H-indices and hms were gathered and computed for clinical neurosurgical faculty at the top 32 ranked academic neurosurgical programs based on the current literature. Hm was computed for faculty at each program, using articles in which the individual was first, second, last, or co-corresponding author. Individuals were further identified based on chair status, leadership status, neurosurgical subspecialty, and National Institutes of Health funding status. Further analysis was performed to determine factors influencing h-index and hm. - RESULTS: The median h-index for the 225 physicians included in the final dataset is 48 (interquartile range [IQR], 39L61), whereas the median hm was 32 (IQR, 24e43). The median difference between h-index and hm is 15 (IQR, 10L23). The median hm/h was 64% (IQR, 57e74). National Institutes of Health funding and subspecialty (neurosurgical oncology, neurocritical care, and cerebrovascular) were associated with significant change from h to hm. - CONCLUSIONS: The h-index can be influenced by noncritical authorship, and hm, using critical contributions, can be used as a complement reflecting critical academic output in neurosurgery. Leaders deciding on hiring or promotion should consider disparities in productivity predicated on noncritical authorship contributions.