Didem Saygin1, Chester V Oddis2, Sedin Dzanko2, Diane Koontz2, Siamak Moghadam-Kia2, Kaveh Ardalan3, Theresa M Coles4, Rohit Aggarwal5. 1. Division of Rheumatology, University of Chicago, Chicago, IL, United States. 2. Division of Rheumatology and Clinical Immunology, University of Pittsburgh Medical Center, BST S 727, 3500 Terrace Street Pittsburgh, PA 15261, United States. 3. Department of Pediatrics, Division of Pediatric Rheumatology, Duke University School of Medicine, Durham, NC, United States; Departments of Pediatrics & Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States; Division of Rheumatology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States. 4. Department of Population Health Sciences, Duke University School of Medicine, Durham, NC, United States. 5. Division of Rheumatology and Clinical Immunology, University of Pittsburgh Medical Center, BST S 727, 3500 Terrace Street Pittsburgh, PA 15261, United States. Electronic address: aggarwalr@upmc.edu.
Abstract
OBJECTIVE: Idiopathic inflammatory myopathies (IIM) are a group of diseases characterized by muscle weakness, which limit activities of daily living. Patient Reported Outcomes Measurement Information System (PROMIS) is a set of outcome measures developed using NIH funding, but has not yet been studied in adult IIM. Currently, the most commonly used PROs in IIM are Health Assessment Questionnaire (HAQ-DI) and SF-36 physical function-10 (PF10), both of which have several limitations. In this study, we investigated psychometric properties of PROMIS physical function-20 (PF-20) and compared to HAQ-DI and SF-36 PF10. METHODS: Patients with IIM completed PROMIS PF-20 and six myositis core set measures [manual muscle testing (MMT), physician (MD-GDA), patient (PT-GDA) and extra-muscular global disease activity, HAQ-DI and creatine kinase], SF-36 PF10 and functional tests [six-minute walk, timed up-and-go and sit-to-stand tests] at monthly visits over 6-months. Total improvement score (TIS) using 2016 ACR/EULAR myositis response criteria was obtained as measures of change. RESULTS: Fifty patients [mean age, 51.6; 60% females] were enrolled; 6 PM, 24 DM, 9 NM and 11 with AS. PROMIS PF-20 showed strong test-retest reliability when repeated in 1-month. PROMIS PF-20 had moderate-strong correlations with MD-GDA, PT-GDA, MMT, HAQ-DI, SF-36 PF10, and functional tests indicating good convergent validity. Change in PROMIS PF-20 strongly correlated with TIS demonstrating good responsiveness. HAQ-DI and SF-36 PF10 exhibited similar validity and responsiveness; HAQ-DI was found to have a ceiling effect. CONCLUSION: PROMIS PF-20 demonstrates favorable psychometric properties in a large cohort of myositis patients and offers distinct advantages.
OBJECTIVE:Idiopathic inflammatory myopathies (IIM) are a group of diseases characterized by muscle weakness, which limit activities of daily living. Patient Reported Outcomes Measurement Information System (PROMIS) is a set of outcome measures developed using NIH funding, but has not yet been studied in adult IIM. Currently, the most commonly used PROs in IIM are Health Assessment Questionnaire (HAQ-DI) and SF-36 physical function-10 (PF10), both of which have several limitations. In this study, we investigated psychometric properties of PROMIS physical function-20 (PF-20) and compared to HAQ-DI and SF-36 PF10. METHODS:Patients with IIM completed PROMIS PF-20 and six myositis core set measures [manual muscle testing (MMT), physician (MD-GDA), patient (PT-GDA) and extra-muscular global disease activity, HAQ-DI and creatine kinase], SF-36 PF10 and functional tests [six-minute walk, timed up-and-go and sit-to-stand tests] at monthly visits over 6-months. Total improvement score (TIS) using 2016 ACR/EULAR myositis response criteria was obtained as measures of change. RESULTS: Fifty patients [mean age, 51.6; 60% females] were enrolled; 6 PM, 24 DM, 9 NM and 11 with AS. PROMIS PF-20 showed strong test-retest reliability when repeated in 1-month. PROMIS PF-20 had moderate-strong correlations with MD-GDA, PT-GDA, MMT, HAQ-DI, SF-36 PF10, and functional tests indicating good convergent validity. Change in PROMIS PF-20 strongly correlated with TIS demonstrating good responsiveness. HAQ-DI and SF-36 PF10 exhibited similar validity and responsiveness; HAQ-DI was found to have a ceiling effect. CONCLUSION: PROMIS PF-20 demonstrates favorable psychometric properties in a large cohort of myositispatients and offers distinct advantages.