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Aiming for the truth: understanding the difference between validity and precision

John R Attia, Michael P Jones and Belinda Suthers
Med J Aust 2016; 205 (9): . || doi: 10.5694/mja16.00489
Published online: 7 November 2016

In teaching generations of registrars, a recurring theme is the conflation of the concepts of validity and precision, resulting in an erroneous understanding of the role of statistics. In this article, we clarify the definition of these two concepts, looking at what drives these measures and how they can be maximised.


  • 1 Centre for Clinical Epidemiology and Biostatistics, University of Newcastle, Newcastle, NSW
  • 2 John Hunter Hospital, Newcastle, NSW
  • 3 Hunter Medical Research Institute, Newcastle, NSW
  • 4 Macquarie University, Sydney, NSW


Correspondence: john.attia@newcastle.edu.au

Competing interests:

No relevant disclosures.

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