1. Coe R. It's the effect size, stupid: what effect size is and why it is important. Paper presented at the 2002 Annual Conference of British Education Research Association, University of Exeter, Exeter, Devon, England, September 12-14, 2002. updated 2015 Sep 6. Available from:
http://www.leeds.ac.uk/educol/documents/00002182.htm.
2. Sullivan GM, Feinn R. Using effect size - or why p value is not enough. J Grad Med Educ. 2012; 4:279–282.