The Complex Regional Pain Syndrome severity score (CSS): Validation and change over time - Rehabilitation Institute of Chicago

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The Complex Regional Pain Syndrome severity score (CSS): Validation and change over time


Investigators have incorporated both signs and symptoms of CRPS into a pragmatic severity score (CSS). This ‘hybrid’ metric is being evaluated as a clinically feasible tool to complement the present/absent dichotomy of diagnosis, particularly for patient monitoring, and for research outcome studies. The overarching aim of this study is to demonstrate the psychometric qualities of the CSS with respect to reliability, validity, and responsiveness to changes in disease course. Well-established, validated indices of global change perception, pain intensity and quality, function and quality of life (QoL), depression, anxiety, and disability due to pain will be measured concurrently. Specifically, this study will evaluate (a) the test-retest reliability of the CSS, (b) the construct validity of the CSS in terms of concurrent validity as reflected in associations with previously validated measures, and (c) the sensitivity of the CSS to intervention, further supporting its construct validity. A statistical analysis plan has been developed to address each of these specific aims.

IRB Protocol Number
Principal Investigator(s)
R. Norman Harden

Clinical Trial Categories

  • Pain Research


  • Provided
Center for Pain Studies at 312-238-5654
Who Can Participate
  • Individuals who meet the 2011 provisional IASP clinical diagnostic criteria (Budapest clinical criteria) for CRPS Type I or II are eligible.


Compensation Provided 

You will receive $80 for first and third visits (new patients);

$100 for first, second, and third visits (established patients)