The 11th revision of the International Classification of Diseases (ICD-11) now includes separate chronic pain diagnoses that may be extended by chronic pain severity specifiers. These specifiers comprise 3 dimensions-pain intensity, pain-related distress, and pain-related interference-rated on an 11-point numerical rating scale referring to the past 7 days. Like the chronic pain diagnoses, these specifiers were originally developed for adults. The current study, therefore, aimed to adapt and validate the 3 ICD-11 chronic pain severity specifiers for pediatric chronic pain patients and evaluate their clinical utility. After adapting the specifiers using feedback from patients and experts, data were collected from N = 319 pediatric chronic pain patients aged 8 to 17 years in a tertiary care setting using 4 assessment methods: patient interview, patient questionnaire, parent-proxy, and healthcare-professional-proxy. Despite all patients having chronic pain, not all reported having experienced pain in the past 7 days. The 3 severity dimensions were interrelated but not unidimensional
both interrater and test-retest reliability were large. While patterns of concurrent and discriminant validity were as expected, correlations with related measures were small. Predictive validity regarding treatment recommendation was small to medium. Most, but not all, suggested severity categories ("none," "mild," "moderate," "severe") were sufficiently distinct within this sample. The chronic pain specifiers provide a quick and easy biopsychosocial description. They should, however, be interpreted with caution in clinical practice, as the psychometric quality is insufficient for making therapeutic or reimbursement-related decisions for individual pediatric patients based solely on these 3 items.