The PAC-SYM questionnaire for chronic constipation: defining the minimal important difference.

Yan YiannakouJ TackH PiessevauxD DuboisEamonn M M QuigleyM Y KeS Da SilvaA JosephR Kerstens

Published in: Alimentary pharmacology & therapeutics (2017)

Anchor-based methods gave consistent results for the minimal important difference, at approximately -0.6, and this value was close to the ROC-determined optimal cut-off scores for responder discrimination. This value could be considered in clinical practice. A slightly more conservative threshold (eg -0.75) could be used in clinical trials to reduce the placebo response rate.

Keyphrases

clinical practice
clinical trial
phase iii
double blind
cross sectional
irritable bowel syndrome
psychometric properties
randomized controlled trial
patient reported
placebo controlled
abdominal pain