Newborn and Infant Nursing Reviews
Volume 10, Issue 1 , Pages 50-54 , March 2010

Interpreting Significance: The Differences Between Statistical Significance, Effect Size, and Practical Importance

  • Pawel Kalinowski, BBSc

      Affiliations

    • School of Psychological Science, La Trobe University
    • Corresponding Author InformationAddress correspondence to Pawel Kalinowski, BBSc, Psychological Science, La Trobe University, Bundoora, Victoria 3086, Australia.
    • ,
  • Fiona Fidler, PhD

      Affiliations

    • School of Psychological Science, La Trobe University
    • Environmental Science, School of Botany, University of Melbourne, Bundoora, Victoria, Australia
    web address

References 

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  2. Cumming G, Fidler F, Leonard M, et al. Statistical reform in psychology: is anything changing?. Psych Science. 2007;18:230
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  6. Maxwell SE. The persistence of underpowered studies in psychological research: causes, consequences, and remedies. Psychol Methods. 2004;9:147–163
  7. Fidler F. From statistical significance to effect estimation: statistical reform in psychology, medicine and ecology. Melbourne, Australia: University of Melbourne; 2006;
  8. Steering Committee of the Physicians' Health Study Research Group. Final report on the aspirin component of the ongoing Physicians' Health Study. N Engl J Med. 1988;321:129–135
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  10. American Psychological Association . Publication manual of the American Psychological Association. 6th ed. Washington (DC): Author; 2009;
  11. Greenland S. Meta-analysis. In:  Rothman KJ,  Greenland S editor. Modern epidemiology. 2nd ed.. Philadelphia: Lippincott-Raven; 1998;
  12. Kazdin AE. The meanings and measurement of clinical significance. J Consult Clin Psychol. 1999;67:332–339
  13. Jacobson NS, Roberts LJ, Berns SB, McGlinchey JB. Methods for defining and determining the clinical significance of treatment effects: description, application, and alternatives. J Consult Clin Psychol. 1999;67:300–307
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  15. Haller H, Krauss S. Misinterpretations of significance: a problem students share with their teachers. Methods Psychol Res. 2002;7:1–20
  16. Kalinowski P, Fidler F, Cumming G. Overcoming the inverse probability fallacy: a comparison of two teaching interventions. Methodology: European Journal of Research Methods for the Behavioral and Social Sciences. 2008;4:152–158
  17. Cumming G. Replication and p intervals: P values predict the future only vaguely, but confidence intervals do much better. Perspect Psychol Sci. 2008;3:286–300
  18. Cumming G, Finch S. Inference by eye: confidence intervals and how to read pictures of data. American Psychologist. 2005;60:170–180
  19. Cumming G, Williams J, Fidler F. Replication and researchers' understanding of confidence intervals and standard error bars. Understanding Statistics. 2004;3:299–311
  20. Belia S, Fidler F, Williams J, et al. Researchers misunderstand confidence intervals and standard error bars. Psychol Methods. 2005;10:389–396

PII: S1527-3369(09)00175-5

doi: 10.1053/j.nainr.2009.12.007

Newborn and Infant Nursing Reviews
Volume 10, Issue 1 , Pages 50-54 , March 2010

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