Measuring the surgical academic output of an institution: the "institutional" H-index

Introduction: The Hirsch index is a novel index that combines the number of publications and citations in measuring the research output of researchers. We hypothesized that the h-index can be used to measure the academic success of an institution in a subject area (surgery) and compared this measure to previously published measures of ranking institutions.

Methods: We identified the top 10 research medical schools as designated by the United States News and World Report 2010. The h-index for an institution was obtained in 3-year periods for articles published in surgery. Independent rankings from the NIH and other web sites were then used to compare with our newly generated rankings.

Results: The median h-index for institutions was 52.5 (46-54) for 2000-2002, 50 (44-52) for 2003-2005, 35.5 (33-40) for 2006-2008, and 15.5 (13-16) for 2009-2011. The percentage of self citations was the highest in publications from Harvard University (22.2%) and the lowest from Columbia University (10%) in the years 2009-11. Our ranking closely mirrored the United States News and World Report, and Harvard Medical School remains the top ranking in the field of surgery, although NIH funding-based ranking may suggest otherwise.

Conclusions: The institutional h-index appears to be a viable indicator for the measure of academic success of institutions in a subject area. Despite limitations, it yields objective data regarding the citations and number of articles published by an institution in a subject area and could be used to measure performance.