Authorship and study characteristic trends in spine publications from years 2004 to 2017

The goal of this study was to analyze the trends in authorship and study characteristics in Spine using two overlapping ten-year time periods: 2004-2014 and 2007-2017. To our knowledge, no other literature reports study characteristics and authorship in the same time period for spine that would allow for the assessment of confounding factors of trends.

Authorship and study characteristic data was collected from all scientific manuscripts published in Spine during the years of 2004, 2007, 2014, and 2017. Basic statistics and Kruskal-Wallis test were used to analyze the data.

We found a significant increase in total number of authors (P<0.0001) without discrepancy of unequivocal increases in author degree type: MD/Equivalent (P≤0.0001), PhD/Doctorate (P=0.0017), Masters (P=0.0015), and Bachelors (P≤0.0001). We observed an increase in industry authorship (P≤0.0001), but without a significant increase in industry funding during the same time span. Increases in administration database studies (P≤0.0001) and economic/value studies (P≤0.0001) were also noted. A significant change in percentage of articles with trauma pathology (decrease, P<0.0001) and deformity (increase, P=0.0002) occurred. The number of multi-institutional studies increased (P≤0.0001), while no change in the number of multi-disciplinary studies.

Increases in author number for spine articles over time are a result of a general increase in authors in all degree types, not just non-doctorate degrees. This may be potentially influenced by the increase in multi-institutional studies. From 2004-2017, higher percentages of articles focus on economics. An increase in industry authorship without a corresponding increase in funding suggests industry's more 'hands-on' approach to publication results from their funded studies.