Assessing the Relevancy of "Citation Classics" in Neurosurgery. Part II: Foundational Papers in Neurosurgery.
BACKGROUND
The second part of this study reanalyzes Ponce and Lozano's (2010) list of classics to create a new list of "foundational" articles in neurosurgery. Ponce and Lozano (2010) previously published a list of 106 neurosurgery classics, as defined by Garfield and his 400 citation criterion.


METHODS
We used the Web of Science citation reports to create graphs for each study showing the total citations it received as a function of time. Each graph was subjectively analyzed independently and scored as "foundational" or "classic only," based on whether the trend of citations received per year was uptrending, neutral, or downtrending.


RESULTS
Of the 101 evaluated classics, 53 qualified as foundational. Over half of these studies were published in Journal of Neurosurgery (13), New England Journal of Medicine (12), or Lancet (5). Grading systems, randomized trials, and prospective studies were most likely to achieve foundational status. Only 30% of functional and 17% of endovascular classics qualified as foundational (compared with 100% of spine classics), suggesting that these fields are rapidly changing or less mature subspecialties still developing a foundational literature base.


CONCLUSION
By assessing citation counts as a function of time, we are able to differentiate classic neurosurgical studies that are critical to modern-day practice from those that are primarily of historic interest. Given the exponential growth of literature in our field, analyses such as these will become increasingly important to both trainees and senior neurosurgeons who strive to educate themselves on the data that drive modern-day clinical decision making.
['Bohl|Michael A|MA|', 'Turner|Jay D|JD|', 'Little|Andrew S|AS|', 'Nakaji|Peter|P|', 'Ponce|Francisco A|FA|']
D015706:Bibliometrics D049673:History, 20th Century D049674:History, 21st Century D006801:Humans D009493:Neurosurgery D011642:Publications
Neurosurgery classics Bibliometric analysis Foundational studies