Validation of Patient-Reported Outcomes Measurement Information System(R) (PROMIS(R)) Pediatric Measures for Children with Chronic Nonbacterial Osteomyelitis

ObjectivesTo assess the validity of the Patient-Reported Outcomes Measurement Information System(R) (PROMIS(R)) Pediatric measures in patients with chronic nonbacterial osteomyelitis (CNO). MethodsWithin the longitudinal patient registry of CNO, English-speaking patients aged 8 years and older self-reported PROMIS Pediatric measures of fatigue, pain interference (PI), pain behavior (PB), mobility, upper extremity (UE), physical activity (PA) and strength impact (SI), and external validation measures. Log-transformed linear mixed-effects models with random patient intercepts were used to assess PROMIS T-score changes. Wilcoxon signed-rank test was performed to determine the PROMIS T-score changes among the improved, worsened, and unchanged groups. Spearman rank correlation test determined the relationship of PROMIS T-scores with disease status reported by patients/families. ResultsMore than 1,000 clinical visits from 184 patients included PROMIS Pediatric measures entries. All PROMIS T-scores correlated significantly (p<0.01) with patient-reported variables and physician global assessment (PHGA). The correlation between function and mobility, PB, and PI was good (r=0.4-0.6). The correlation of patient-reported disease status was strong with PHGA (r=0.75), moderate with mobility, PB, PI, and weak with Fatigue, SI, UE, and PA. The changes of PROMIS T-scores over time for mobility, PB, PA, and PI compared to the self-reported status change were significant (p<0.05). After effective treatment, when clinical disease activity score improved by at least 2.5 points (n=18), the change of PROMIS T-scores for mobility, PB, PI, UE were significant (p<0.05). ConclusionThis study provided evidence supporting the use of PROMIS Pediatric mobility, pain behavior, and pain interference measures for CNO clinical disease monitoring. Key MessagesPROMIS Pediatric measures are valid tools for assessing disease burden in patients with Chronic Nonbacterial osteomyelitis (CNO); T-scores across all domains showed significant correlations with patient-reported outcomes and physician global assessments, with particularly strong correlations for mobility, pain behavior, and pain interference. PROMIS Pediatric T-scores for mobility, pain behavior, physical activity, and pain interference were sensitive to patient-reported changes in disease status over time, supporting their use in tracking disease progression in CNO. Following effective treatment, defined by at least a 2.5-point improvement in clinical disease activity score, PROMIS Pediatric T-scores for mobility, pain behavior, pain interference, and upper extremity function showed significant improvement, highlighting their responsiveness to treatment in CNO.