There is increasing interest in the growing number of new indices for scholarship assessment (Jackson et al. 2009, Thompson et al. 2009). Following our recent editorial on rating research performance, specifically the h-index (Thompson & Watson 2009), we thought it would be interesting to see how professors of nursing are ranked by this measure.
The h-index rates academics’ performance based on their career publications, as measured by the lifetime number of citations each article receives. The h-index depends on both the number of publications and number of citations of these publications; specifically, as defined by its originator Hirsch (2005, p. 16569):
A scientist has index h if h of his/her Np papers have at least h citations and the other (Np–h) papers have no more than h citations each.
h-Indices can be obtained through the Thomson ISI Web of Science (http://www.isiknowledge.com), Scopus (http://www.scopus.com) or Publish or Perish (http://www.harzing.com/pop.htm) although the h-index depends on the number of journals covered by, for example, Web of Science, and the time span. It is our experience that Web of Science provides the most stable and conservative measure of the h-index.
For the purpose of this exercise, we identified 16 leading nurse and midwife professors in the UK from their role as either a member of the 2008 UK Research Assessment Exercise or as one of the three nurses or midwives appointed as a NIHR senior investigator (http://www.nihr.ac.uk/faculty/Pages/faculty_senior_investigators_directory.aspx).
We calculated each person’s h-index using Web of Science. To ensure transparency, and to correct for any error, we invited individuals to check, and where necessary (providing evidence) correct, their h-index. They were given one month to respond to our ratings. Individuals, their current institution and their h-index are shown in Table 1. Both authors checked these data simultaneously at midday on 11 March 2010.
|Charlotte Clarke||University of Northumbria||4|
|Karen Cox||University of Nottingham||8|
|Nicky Cullum||University of York||15|
|Martin Johnson||University of Salford||4|
|William Lauder||University of Stirling||7|
|Karen Luker||University of Manchester||19|
|Jill Macleod Clark||University of Southampton||9|
|Hugh McKenna||University of Ulster||14|
|Ruth Northway||University of Glamorgan||3|
|Anne Marie Rafferty||King’s College London||8|
|Mary Renfrew||University of York||18|
|Kate Seers||Royal College of Nursing||14|
|David Thompson||University of Leicester||22|
|Caroline Watkins||University of Central Lancashire||9|
|Roger Watson||University of Sheffield||15|
|Anne Williams||University of Cardiff||8|
We appreciate that there are limitations to the use of h-indices: they are continually being raised and never decline over a lifetime, but this analysis gives a ‘snapshot’ of current performance. It also gives an indication of success. Hirsch (2005) suggested that, after 20 years, an h-index of 20 is a sign of success, and one of 12 should be good enough to secure tenure. Judged from this ‘snapshot’, nurse professors (many with significant experience) fall significantly short of this particular yardstick. Only eight have h-indices exceeding 10. However, this does not mean that any or all of the aforementioned professors of nursing are poorly published or poorly cited in general (although these data can also easily be obtained); however, it does indicate that, generally, there is a lack of contribution to the field – as estimated by the h-index- in terms of sustained bodies of work that include a large number of papers in one area that, consequently, receive a high number of citations.
Nevertheless, as Hirsch (2005) indicated, h-indices are likely to be discipline and subject specific and the above, possibly, provides an indication of the situation regarding citation patterns in nursing. It also, surely, stems in the UK from the difficulty of obtaining sustained levels of funding in one area of research and this could easily be tested by comparing h-indices with North America where more sustained and, generally, greater amounts of research funding are available. Potentially, therefore, it provides a baseline for the performance of nursing professors in the UK and a way of comparing ourselves internationally; the information is easily obtained and in the public domain. Ultimately, we envisage that some standards could be set regarding h-indices as an aid to the appointment, promotion and reward of professors of nursing. We venture to make a start here.
We propose that h-indices in nursing generally are low compared with other subjects. Therefore, the yardstick provided by Hirsch may be inapplicable in our field. Based on the data available here – and fully appreciating that this could and should be subject to revision in the light of further national and international data – the mean h-index is 11. We could say that, against a potentially low value of h-indices in UK nursing, and with the range presented here, that professors of nursing should, at the very least, have an h-index. In other words, they should not have an h-index of zero and this applies equally to those who could be described – tautologically – as research professors or those appointed by other routes such as teaching. Lack of research activity should be no excuse for not making a contribution to one’s field through scholarship and publication in refereed journals. In terms of an actual figure, and one that does not take into account years of activity before and after a professorial appointment, we suggest that an h-index in the region of 10 may be an appropriate indicator of success in our field at this time. Nevertheless, this figure is low when you consider that an h-index of 10 means that you have 10 pieces of published work that have been cited at least 10 times, regardless of the number of citations to individual pieces of work that have a much higher citation rate and a considerable ‘tail’ of publications that have been cited fewer times.
We may have a problem in academic nursing regarding contribution to our field as estimated by the h-index, and we may need to find a solution. We can claim some subject specificity regarding our field and the citation patterns in it; but not for long. Other cognate fields, where h-indices are much higher (we have identified one leading UK psychologist with an h-index of 46 and over 10,000 citations to his work) will look at us and wonder why we compare so unfavourably. Other than deliberate manipulation of individual h-indices, the solution may lie in ensuring that our work is more easily available and internet sites such as Researcher ID, which is based on the Web of Science, and publicationslist.org provide this opportunity. At least, registering with this site, and doing the initial search of Web of Science that is necessary, will let individuals see their own h-index, which papers are contributing to it and what work needs to be cited to raise it. While this is open to manipulation it also, potentially, guides individuals to focus on one field of research where they are gaining a reputation, in which they have been successful and on which a sustained body of work can be built. The h-index may even help them to obtain funding.
In conclusion, h-indices are low in nursing; this may or may not be of concern to the profession but we advocate concern both for what it indicates and for what it could lead to if addressed, including greater recognition by other fields. At a time when the UK process of research assessment, now called the Research Excellence Framework (Nolan et al. 2008), is committed to incorporating citation metrics into its criteria for judgment of quality and contemplating the means to do this (probably not using h-indices), it is an appropriate time for us to consider what our citation patterns in nursing indicate about our field and what, if any, the consequences will be of leaving things as they are.