From the editors’ desk| Volume 97, ISSUE 7, P1051-1052, July 2016

What to Do With “Moderate” Reliability and Validity Coefficients?

  • Marcel W. Post
    Corresponding author Marcel W. Post, PhD, De Hoogstraat Rehabilitation, Rembrandtkade 10, 3583TM Utrecht, The Netherlands.
    University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen; and Brain Center Rudolf Magnus and Center of Excellence in Rehabilitation Medicine, University Medical Center Utrecht and De Hoogstraat, Utrecht, The Netherlands
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Published:April 16, 2016DOI:


      Clinimetric studies may use criteria for test-retest reliability and convergent validity such that correlation coefficients as low as .40 are supportive of reliability and validity. It can be argued that moderate (.40–.60) correlations should not be interpreted in this way and that reliability coefficients <.70 should be considered as indicative of unreliability. Convergent validity coefficients in the .40 to .60 or .40 to .70 range should be considered as indications of validity problems, or as inconclusive at best. Studies on reliability and convergent should be designed in such a way that it is realistic to expect high reliability and validity coefficients. Multitrait multimethod approaches are preferred to study construct (convergent-divergent) validity.


      List of abbreviations:

      ICC (intraclass correlation coefficient), RMD (Rehabilitation Measures Database), SCIRE (Spinal Cord Injury Rehabilitation Evidence)
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