Open letter for a professional association regarding impact factors

By John Pickering 03/07/2013

Dr John Pickering
Department of Medicine
University of Otago Christchurch
New Zealand
Dr Peter Kerr
Journal of the Asia Pacific Society of Nephrology

3 July 2013

Re:  Open letter regarding the Nephrology journal’s use of impact factors

Dear Dr Kerr

As an occasional referee for Nephrology and member of the ANZSN affiliated with the APSN I write concerning Nephrology’s use of the Thomson Reuter’s Impact Factor and the journal rankings based on them.  Specifically I urge that Nephrology remove the Impact Factor and ranking from the journal web site.  This is because the continued use of Impact Factors reflects poorly on the integrity of the journal and the APSN.  My reasons are:

(i)            Regularly when refereeing I have to ask authors to present medians and interquartile ranges rather then means and standard deviations when the distribution of the variable they are measuring is not normally distributed.  The Impact Factor is the mean of a very highly skewed distribution and, as such, it is a nonsense statistical metric.

(ii)          Rankings on the basis of the mean of a skewed distribution are similarly a nonsense metric.

(iii)         Impact Factors are open to manipulation.  See:

Nature 2013:

Science Feb 2012:

(iv)         Professional associations have begun to recognise the inherent flaws in how research is assessed.  In particularly a world-wide movement initiated by the American Association of Cell Biology, namely the San Francisco Declaration on Research Assessment (DORA), has identified some much needed standards to maintain integrity for scientists and associated professional associations.  See



cc. Dr Yasuhiko Tomino, President Asia Pacific Society of Nephrology (APSN)
Dr Rowan Walker, President Australia New Zealand Society of Nephrology (ANZSN)
Any interested party may read this letter through or

Tagged: Impact Factors, Nephrology, Professional Association