Pediatric chronic pain grading: a revised classification of the severity of pediatric chronic pain

In this study, we describe the development and validation of a revised Pediatric Chronic Pain Grading (P-CPG) for children aged 8 to 17 years that adds emotional impairment to previously used measures of pain intensity and functional impairment. Such a measure enables the assessment of chronic pain severity in different epidemiological and clinical populations, the stratification of treatment according to pain severity, and the monitoring of treatment outcome. The P-CPG was developed using a representative sample of school children with chronic pain (n = 454; M age = 12.95, SD = 2.22). Construct validity and sensitivity to change were examined within a sample of N = 2448 children and adolescents (M age = 12.71, SD = 2.47) comprising 3 subsamples (school n = 1562, primary care n = 129, and tertiary care n = 757) affected by chronic pain to varying extents. Results showed that P-CPG grades differed significantly among the 3 subsamples, with school children being least affected by chronic pain and tertiary care patients being most affected. As P-CPG grade increased, so did pain intensity, functional impairment, pain-related school absence, and emotional impairment. Convergent validity was demonstrated by significant positive correlations between the P-CPG and global ratings of pain severity as well as objective claims data; the latter reflects greater health care costs with increasing P-CPG scores. Sensitivity to change was supported by a significant reduction in baseline P-CPG grades 3 and 6 months after intensive interdisciplinary pain treatment in tertiary care sample. In conclusion, the P-CPG is an appropriate measure of pain severity in children and adolescents with chronic pain in clinical as well as epidemiological settings.