Measuring Academic Output: The H-Index

Most of us in academic positions have been promoted mainly based on the number of our publications, particularly those appearing in peer-reviewed journals. A problem with this type of evaluation is that it is subjective: it generally measures quantity more than quality. Additionally, other sources

most of the work you should be listed first, and if you were the second person who did most of the work, you should be listed as the last author! Remember, too, that many publications submitting to Google Scholar use initials rather than first names, so searches may yield articles from a variety of authors who share first initials and last names. Despite these caveats, comparison of h-indices obtained by using Google Scholar and Scopus correlate highly. 3 Google Scholar is probably more inclusive than ISI's Web of Science and thus it may result in a better h-index calculation. (Although this is true for engineering, business, and social sciences, it is questionable for the health sciences.) However, Google Scholar does not totally capture articles in languages other than English (so-called LOTE articles) and citations in chapters and books, and therefore it may underestimate h-indices.
Although there are other indices, the h-index, at least for now, provides a robust single metric that combines quality and quantity. Attempts to normalize the h-index across disciplines have met with mixed results. The g-index aims to improve it by giving more weight to highly cited articles. 5 The e-index strives to differentiate between scientists with similar h-indices with different citation patterns. 6 For those who are interested in assessing a constant level of academic activity, the contemporary h-index gives more weight to recent articles. 7 The AW-index (age-weighted) adjusts for the age of each individual paper. (The older you are the higher your h-index will be.) 8 The multi-authored h-index modifies the original metric by taking into account shared authorship of articles. Though all are improvements on the initial h-index, the original metric is still the most widely used.
I decided to calculate the h-index for the senior neuroradiology editors for the American Journal of Neuroradiology (AJNR) and 2 other major imaging journals (American Journal of Roentgenology [AJR] and Radiology). I did not calculate the h-index for the Editors-in-Chief as our subspecialties and ages vary, and, as earlier stated, these are caveats. (To be fair, I need to state that the Editor of Radiology has the highest h-index of the 3 of us.) For these calculations, I used the Harzing Publish or Perish software, which is freely available on the Internet 9 and also ISI Web of Knowledge. 1 In my search I included all fields related to imaging by using the last names of these individuals followed by their first and middle initials. Using the Harzing software, when individuals with similar names ensued, I manually selected only the articles desired. Although my calculations may be fraught with some errors, I think that they provide an adequate overview of the utility of the h-index. Figure 1 shows the h-indices of all Senior Editors by using the Harzing method; the person with the highest index works for AJNR, closely followed by the individuals in AJR and Radiology. Note that all individuals showed scores of 20 or higher, which are considered to be very good. Using the ISI Web of Knowledge method, similar trends were observed though most scores were a bit lower (Fig 2). If one averages the hindices of Senior Editors per journal by using the Harzing and ISI methods, the results are as follows: AJNR (34 and 32), AJR (30 and 24.5), and Radiology (32.5 and 28); again very similar among journals but slightly lower by using the second method. Scores tend to be higher using the Harzing method because it utilizes Google Scholar data which are more inclusive than those found in the ISI database. Because the h-index tends to EDITORIALS AJNR Am J Neuroradiol 31:783-86 ͉ May 2010 ͉ www.ajnr.org be higher for older individuals, it was not surprising that the highest scores were for the more senior of the editors.
Needless to say, I was gratified to find out how well AJNR did when compared with such respected journals as AJR and Radiology. Our contributors and readers can rest assured that AJNR's contents are being handled by the most qualified neuroradiologists.

Neuroradiology without Benefit of Computers: A Memoir
A t 73 years of age, I feel fortunate still to be engaged in the full-time practice of neuroradiology, quite a different discipline today from the one for which I was trained. As one of the few remaining members of our specialty who trained in the pre-CT era (before August 1973), I thought I might share with those who have come later some reminiscences about what we did in our fellowships and practices before the "cross-sectional revolution." Following a rotating internship, a 2-year interval for active duty as a general medical officer in the US Navy, and a 3-year residency in general radiology (therapy and diagnosis) at the "late" Philadelphia General Hospital (PGH), I followed in the footsteps of 4 previous PGH residents, Freddie Gargano, Bassett Kilgore, E. Ralph Heinz, and Irvin Kricheff, in opting for a fellowship in neuroradiology with the late Juan Taveras I arranged to fly out to St. Louis for an interview and, needless to say, was impressed with the personal attention I received from Dr. Taveras. I was surprised to learn that the program was a 2-year commitment and that I would be expected to do procedures such as arteriography, not just interpret them. In the 1960s at PGH, arteriograms were done by residents on clinical services with little or no supervision and had more morbidity than I would have wanted to be associated with. I returned to Philadelphia that night, and the next day my chief called Taveras, who told him that he would accept me as a fellow the following year (there was no matching program for fellowships at that time).
A few days later, I received an acceptance letter telling me to apply to the National Institute of Neurologic Diseases and Blindness for a "Special Fellowship in Neuroradiology" and to tell them that I had already been accepted by Dr. Taveras, which would guarantee that it would be awarded to me. This fellowship provided me with an annual pretax salary of $12,000, out of which I was supposed to live, pay taxes, and move my family to St. Louis. I was fortunate to have a supplement of $360 per month from the G.I. Bill, and by some miracle, my family managed to live a normal life. Moonlighting was only permitted when we were on vacation.
There were basically 3 rotations in the program: 1) arteriography, 2) pneumoencephalography and Pantopaque myelography, and 3) supervision of resident readings of plain skull, spine, and head and neck studies, including monitoring of hypocycloidal tomography. In the second year, fellows were periodically assigned to do arteriography at St. Louis City Hospital, where we supervised a senior resident.
One afternoon a week, I would go to the library and skim current issues of journals, jotting down the titles and authors of interesting articles to write postcards for reprints. There was no