Questions and answers The aim of this section is for you to identify and try to answer puzzles, especially methodological ones, in health services research and policy. Readers are invited both to submit questions, which they think will be of general interest or which are particularly topical, and to offer answers to questions. Questions can be ones that you feel have not been satisfactorily answered in the existing literature, ones that relate to ‘self-
evident’ definitions which need to be made problematic, or paradoxes. Please send your questions to: Gillian Parker, SPRU, University of York, Alcuin College, Heslington, York YO10 5DD, UK. Email:
[email protected]. Fax: 144 (0)1904 321953.
Does a citation rating tell you whether an article is useful?
first glance, a citation rating could be considered as a quality indicator – but does the number of citations really tell you anything about the quality of a scientist’s work? Is fast food of good quality because we eat a great deal of it? No doubt, a citation rating can tell us whether articles attract more or less interest within the scientific community. However, there are three aspects that are essential to take into consideration:
What citation rating do you mean? There is the recently established AppleTM citation rating and there is the venerable Lemon w citation rating. An article published in 2002 in the journal I edit has 40 citations on the AppleTM citation rating – admittedly 12 of them were author selfcitations. However, the same article has zero citations on the Lemon w list! Why the difference? Well Lemon w does not include the journal in its source list while AppleTM does. As a consequence, the article is very useful if you want to eat it but no use at all for squeezing. Authors who publish in my journal find Alpher, Bethe and Gamow’s 1948 article, ‘The Origin of Chemical Elements’ in the Physical Review so useful that they cite it often. However, none of these citations make it into the Lemon w index while they all appear in the AppleTM index. Not surprisingly, the article’s authors prefer to state their AppleTM citation rating. But are these articles useful? You need to realize that citation ratings are a moveable feast and that some people prefer a lemon tart to an apple pie. Don’t let the citation rating determine an article’s reputation. Rather decide for yourself whether an article is of use to you. Martin Caon Senior Lecturer in Biophysical Science School of Nursing and Midwifery Flinders University GPO Box 2100, Adelaide 5001, Australia
An article ranking highly in a citation rating can be useful but it can also be of no avail at all for you. Reflecting on criteria concerning usefulness of articles may help to answer the question. Besides the reader’s specific interest in a topic the quality of the paper is the most important criterion. At
DOI: 10.1258/jhsrp.2008.080001
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You may find an article very useful even though it is published in a less prestigious journal that is, on average, not frequently cited; High numbers of citations do not indicate the impact an article has on science; Citation ratings can significantly suffer from publication bias.
The CONSORT statement checklist offers criteria that are more meaningful in order to assess the quality and usefulness of an article.1 It is also worth checking the statement on conflicts of interest which is, one hopes, published with an article.2 The information you get from this may seriously alter your decision on whether an article is really useful for you. Nils Schneider Department of Epidemiology, Social Medicine and Health System Research Hannover Medical School Carl-Neuberg-Str. 1 30625 Hannover, Germany
References 1 CONSORT. Transparent reporting of trials. See http://www. consort-statement.org (updated October 2007) 2 International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. See http://www.ICMJE.org (updated February 2006)
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