Importance of First and Second Authorship in Assessing Citation-Based Scholarly Activity of United States Radiation Oncology Residents and Subsequent Choice of Academic versus Private Practice Career

Abstract

The Hirsch index (h-index) has become increasingly popular in assessing citation-based scholarly activity of physicians, and has been shown to correlate with Radiation Oncology residents having a first job in academics versus private practice. A limitation of the h-index methodology is its inability to distinguish between the differing significance of co-author roles in manuscripts (i.e. first author versus fifth author). This study was performed to assess the role of first and second author publications and their association with resident pursuit of academic versus private practice career. A list of 2016 radiation oncology resident graduates (163 residents from 76 Accreditation Council for Graduate Medical Education-certified programs) and their post-residency career choice (academic versus private practice) was compiled as previously described (McClelland et al., Practical Radiation Oncology 2017). The SCOPUS bibliometric citation database was then searched to collect h-index data for manuscripts limited to first-author only (hf) and first or second-author only (hs) for each resident. Demographics included in analyses were gender and PhD degree status. The mean hf was 2.06 for all resident graduates; mean hs was 2.77. Residents with a PhD had significantly higher hf (3.11 versus 1.76; p<0.01) and hs (4.50 versus 2.28; p<0.01). There was no statistically significant difference between male and female residents fpr hf (2.19 versus 1.61; p=0.11) or hs (2.91 versus 2.25; p=0.15). With regard to career choice, residents going on to academic jobs had higher hf (2.72 versus 1.44; p<0.01) and hs (3.57 versus 2.01; p<0.01) than those choosing private practice. Less than 20% of graduates with hf of zero chose academic careers, and only 10% of graduates with hs of zero went on to academic jobs. The average radiation oncology resident graduate has published a minimum of two first and/or second-author manuscripts cited at least twice. As with the traditional h-index, graduates with a PhD and/or choosing academic careers are more likely to have higher hf and hs scores, and there is no significant difference in scores between male and female residents. Noteworthy is that only 10% of graduates without any first and/or second-author manuscripts cited at least once went on to academic jobs. These findings indicate that stratifying publications by first or second authorship when developing benchmarks for evaluating both radiation oncology resident productivity and post-residency career choices may be useful. This work represents the first demonstration of these assessment measures in radiation oncology, and show that they are well associated with post-residency career type. Consequently, these measures deserve further study.