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p < .05 — But Is It Clinically Significant? Practical Examples for Clinicians

Published online by Cambridge University Press:  06 October 2014

Stephen Matthey
Stephen Matthey*
Affiliation:
South West Sydney Area Health Service
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Extract

Many researchers report the p value of an analysis to communicate whether findings are significant. This may be misinterpreted to imply that if p < .05 the finding is also of clinical significance. Researchers should also report the magnitude of the association, an easily calculated statistic, to allow a better understanding of results when p < .05. Methods for doing this for t, χ2, and F values are given. The clinical significance of an intervention is also commonly determined by whether p < .05. A better understanding, however, is gained by then calculating the effect size (d). This measure enables effects and strengths of association to be compared among studies. Methods for doing this, for the same statistics, are given.

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Type
Research Article
Information
Behaviour Change , Volume 15 , Issue 2 , June 1998 , pp. 140 - 146
Copyright
Copyright © The Author(s) 1998

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