Patient global impression of change in pediatric chronic pain clinical trials: A review and secondary analysis of randomized controlled trial data

Abstract

The Patient Global Impression of Change (PGIC) is a single-item self-report measure commonly used in adult pain clinical trials to assess patients’ perceived overall change since treatment initiation. Its use is recommended in pediatric pain clinical trials as well. Through a targeted literature review and secondary analysis of PGIC use and performance in pediatric chronic pain trials, we aimed to expand knowledge of PGIC measures in youth with chronic pain (10.17605/OSF.IO/9P6HY). The targeted review identified 13 trials employing two global change scales—PGIC and Global Rating of Change (GROC)—with substantial inconsistency in item wording, anchors, and response formats. For empirical testing, we conducted secondary analysis of two randomized controlled trials of psychological interventions for youth with chronic pain, specifically: youth with mixed chronic pain (n=143) (WebMAP Mobile Trial), and youth with sickle cell pain (n=111) (iCC-SCD Trial). Longitudinal convergent validity was tested as incremental variance in outcomes explained by PGIC beyond covariates, and responsiveness as intervention–control differences across PGIC categories. In the first trial, PGIC explained ¡ additional variance in both pain and psychological outcomes and discriminated between the intervention and control groups; in the second trial, PGIC explained additional variance in psychological but not pain outcomes and did not differ between groups. Collectively, findings highlight the variability in implementation of global change measures in pediatric chronic pain trials and provide preliminary validation for one PGIC version. Standardization and further validation, particularly content validity, clarifying anchors, category thresholds, and recommended analytic approaches, are needed.