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.