Pain Measurement in Children with Functional Abdominal Pain.

Functional abdominal pain (FAP) occurs frequently in pediatric patients. Lacking clear biomarkers, clinicians and researchers must rely on patient reports of pain intensity. Presently, there are challenges affecting our ability to use existing measures of self-reported pediatric pain intensity. This report discusses those challenges, finding that: (a) inter-rater agreement of children's pain intensity is generally low; (b) typically used approaches to measuring outcomes may yield high levels of unreliable reports of improvement; (c) a distribution-based approach involving the calculation of a reliable change index can produce results that classify individuals as improved reliably, but this approach needs to be combined with another approach that ensures the findings will be clinically meaningful as well; (d) clinical trials for FAP rarely report findings about how many individuals improve in a statistically reliable, clinically meaningful manner; and (e) more information about the test-retest reliability of commonly used measures is needed to accurately gauge treatment-related improvement.