CONSTRUCT VALIDITY AND RESPONSIVENESS OF PROMIS (R) MEASURES IN JUVENILE IDIOPATHIC ARTHRITIS AND CHRONIC MUSCULOSKELETAL PAIN

Background In an effort to improve the efficiency and advance the science of patient-reported outcomes (PRO) assessment in chronic diseases, the US National Institutes of Health has created a cooperative network of researchers to develop new PRO measures using item response theory, resulting in the Patient Reported Outcomes Measurement Information System (PROMIS®). Objectives To evaluate the construct validity and responsiveness of the PROMIS pediatric measures with longitudinal assessments in JIA and chronic musculoskeletal (MSK) pain patients. We hypothesized the PROMIS measures of Fatigue, Mobility, Pain Interference, and Upper Extremity function (UE) would discriminate between levels of condition severity. Methods Patients 8-18 years old were recruited for this study from two large academic US children’s hospitals. Inclusion criteria were: diagnosed with JIA or chronic MSK pain, fluent in English, and able to interact with a computer. Patients were recruited if a change in clinical status was anticipated over time. Participants completed PROMIS scales (mean=50; SD=10) on the computer and legacy measures on paper at 3 regularly scheduled clinic visits, on average 4.3 months apart. Results 121 JIA participants (mean age=13.0) were recruited. Majority (86) were female (71.1%); 84 had polyarthritis (69.4%), 16 oligoarthritis (13.2%), 11 systemic (9.1%), and 10 other (8.3%). 110 (90.9%) completed all 3 assessments. A number of PROMIS scales and legacy measures were highly or moderately correlated at baseline ([Table 1][1]). Differences in average scores on PROMIS measures were demonstrated between participants with oligo-, poly- and systemic JIA categories, with systemic patients having lower Mobility scores (F=4.63, P=.01), lower UE scores (F=4.25, p=.02), higher Pain Interference scores (F=4.22, P=.02), and higher Fatigue scores (F=3.83, P=.02). Responsiveness of PROMIS measures was demonstrated by change in mean score (SD) over the 3 assessments with treatment. For Fatigue: 47.5 (12.48), 43.49 (12.26), 42.13 (13.72); Pain Interference: 51.1 (8.83), 47.72 (10.23), 46.37 (11.26); Mobility: 44.51 (9.78), 47.14 (9.87), 48.3 (11.12) and UE: 45.66 (9.61), 47.82 (8.9), 48.08 (9.94). 146 chronic MSK pain patients (mean age=15.1) were recruited. Majority (122) were female (83.6%); 67 had Generalized MSK pain (45.9%), 32 Lower Extremity pain (21.9%), 6 Upper Extremity pain (4.1%), 2 Upper and Lower Extremity pain (1.3%), 36 Back pain (24.7%), and 3 Neck pain (2.1%). Over 3 study visits, movement in mean scores (SD) across PROMIS® measures was observed. For Fatigue: 60.48 (12.55), 53.43 (14.29), 50.81 (15.33); Mobility: 35.59 (7.11), 41.62 (9.65), 44.31 (11.81); Pain Interference: 62.14 (7.1), 56.4 (10.53), 52.97 (12.21); and UE: 40.99 (9.55), 44.96 (10.46), 48.29 (10.21). ![Figure][2] Conclusions PROMIS pediatric measures demonstrated construct validity and were responsive to change in disease activity in cohorts of patients with JIA and Chronic MSK pain. Acknowledgements Funded by NIH NIAMS Cooperative Agreement Award U01AR057940. Disclosure of Interest J. Farrell: None Declared, B. Huang: None Declared, A. Carle: None Declared, S. Kashikar-Zuck: None Declared, K. Barnett: None Declared, E. Morgan DeWitt Grant/research support from: National Institutes of Health [1]: #F1 [2]: pending:yes