2146 The Journal of Rheumatology 2006; 33:11 Personal non-commercial use only. The Journal of Rheumatology Copyright © 2006. All rights reserved. An Index of Patient Reported Outcomes (PRO-Index) Discriminates Effectively Between Active and Control Treatment in 4 Clinical Trials of Adalimumab in Rheumatoid Arthritis THEODORE PINCUS, CECILIA CHUNG, OSCAR G. SEGURADO, INGRID AMARA, and GARY G. KOCH ABSTRACT. Objective. To analyze 2 indices composed of the 3 patient reported outcomes (PRO) in the American College of Rheumatology (ACR) Core Data Set — physical function, pain, and global estimate — with- out joint count or laboratory data, for capacities to distinguish active from control treatments in 4 pivotal clinical trials. Methods. Data from 4 clinical trials involving adalimumab, in combination with methotrexate or other disease-modifying antirheumatic drugs (DMARD) or as monotherapy, versus control treatment were made available to analyze properties of various indices. A categorical PRO-Index M was defined as “majority” improvement in 2 of the 3 PRO measures at 20%, 50%, and 70% levels; results were eval- uated to analyze agreement with ACR20, ACR50, ACR70 responses and an “all Core Data Set meas- ures” index based on 4 of the 7 measures having such levels of improvement. A continuous PRO-Index C was defined as the median or 2nd highest of 3 percentage differences from baseline to endpoint; results were evaluated to analyze agreement with a continuous ACR-N, “all Core Data Set measures” index, and Disease Activity Score 28 (DAS28). Results. All indices distinguished active versus control treatment at similar levels, including PRO-Index M versus ACR20, ACR50, and ACR70 responses, and PRO-Index C versus DAS28. Conclusion. PRO indices based only on patient questionnaire data, without joint counts or laboratory tests, may be useful quantitative measures of therapeutic efficacy for use in standard rheumatology clin- ical care. (First Release Oct 15 2006; J Rheumatol 2006;33:2146–52) Key Indexing Terms: QUESTIONNAIRES RHEUMATOID ARTHRITIS RANDOMIZED CONTROLLED TRIAL ADALIMUMAB PATIENT INDEX From the Vanderbilt University Medical Center,Nashville, TN; Abbott Laboratories, Abbott Park, IL; Quintiles, Inc., Durham, NC; and the University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. T. Pincus, MD, Professor of Medicine; C. Chung, MD, PhD, Vanderbilt University Medical Center; O.G. Segurado, MD, PhD, Abbott Laboratories; I. Amara, DrPH, Quintiles, Inc.; G.G. Koch, PhD, University of North Carolina at Chapel Hill. Address reprint requests to Dr. T. Pincus, Division of Rheumatology and Immunology, Vanderbilt University School of Medicine, 203 Oxford House, Box 5, Nashville, TN 37232-4500. E-mail:t.pincus@vanderbilt.edu Accepted for publication June 6, 2006. The American College of Rheumatology (ACR) Core Data Set 1-3 and Disease Activity Score 28 (DAS28) 4,5 are major advances to standardize measurement in rheumatoid arthritis (RA) clinical trials and other clinical research. Criteria based on 20%, 50%, and 70% improvement in ACR Core Data Set measures (ACR20, 50, 70) have been developed for clinical trials 6 . The ACR response criteria represent change scores from baseline to endpoint, and cannot be used as an absolute clinical measure. DAS scores have an absolute value rather than being based on change, and are useful in both clinical tri- als and standard clinical care. These indices are advances used primarily to assess RA in clinical trials and clinical research. Most standard rheumatol- ogy clinical care, however, is conducted according to empiri- cal qualitative impressions rather than quantitative clinical measurement. Formal quantitative joint counts, although regarded by rheumatologists as the most important means to assess RA 5 , and needed to calculate ACR criteria or a DAS, generally are not performed at most visits of patients with RA to most rheumatologists 6 . The only quantitative measure recorded at most visits is a laboratory test such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), which may be normal in 40% of patients 7 . Therefore, ACR criteria or a DAS generally are not available in standard rheumatology care, despite an excellent website (www.das-score.nl) and cal- culators that simplify computation of the DAS. A pragmatic quantitative measure that does not require joint counts or laboratory tests, for which the patient does almost all the work, might be of value to rheumatologists and their patients in standard clinical care. Three of the 7 compo- nents of the ACR Core Data Set, physical function, pain, and global estimate, are patient reported outcome (PRO) meas- ures. A quantitative index of only these 3 patient self-report www.jrheum.org Downloaded on January 21, 2023 from