Application of Explicit Process of Care Measurement to Rheumatoid Arthritis: Moving from Evidence to Practice K. L. KAHN, 1 C. H. MACLEAN, 2 H. LIU, 3 L. Z. RUBENSTEIN, 4 A. L. WONG, 5 J. O. HARKER, 6 W. P. CHEN, 3 D. M. FITZPATRICK, 3 K. J. BULPITT, 7 S. B. TRAINA, 3 B. S. MITTMAN, 6 B. H. HAHN, 3 AND H. E. PAULUS 3 Objective. To construct quality measures with measurement validity and meaning for clinicians. Methods. We conducted a prospective cohort study of rates of change in disease-modifying antirheumatic drug (DMARD) and/or systemic corticosteroid drug or dose for 568 patients with rheumatoid arthritis (RA) across 6,159 clinical encounters within 12 months to examine how changes in clinical specifications change adherence. Results. Rates of DMARD change were sensitive to specifications regarding the intensity of disease activity (severe or moderate), duration of specified disease activity, and length of the observation period. Over 12 months, the proportions of 377 patients with severe disease activity observed for 1-month, 2-month, and 3-month time blocks who had a change in DMARD drug or dose were 36%, 57%, and 74%, respectively. Over 12 months, a change in DMARD drug or dose was observed for 44%, 50%, and 68% of 377 patients with severe disease within 3 months, 6 months, and 12 months, respectively, of the patient meeting criteria for severe disease activity. A change in DMARD drug or dose was observed for 21%, 23%, and 34% of 149 patients with moderate disease activity within 3, 6, and 12 months, respectively, of the patient meeting criteria for moderate disease activity. Conclusion. Rates of pharmacologic interventions for patients with moderate and severe RA disease activity vary substantially by intensity and duration of disease activity and by duration of period for observing change. Lack of precision in explicit process criteria could substantially mislead comparisons of quality of care across comparison groups. KEY WORDS. Rheumatoid arthritis; DMARDs; Quality of care. INTRODUCTION Explicit process measurement is used to assess whether patients receive services they need. The most rigorous means for establishing need is demonstration of improved outcomes among patients who receive a service as com- pared with those who do not. When available, the results of randomized controlled trials can be used to inform the construction of explicit process measures (1). But trials are often conducted for a select homogenous cohort of patients not representative of the patients who span the quality of care spectrum (2). Therefore, even when trials provide evidence regarding the efficacy of an intervention for one Supported by the NIH (grant 5 P60-AR-36834) and the University of California, Los Angeles Multipurpose Arthritis and Musculoskeletal Disease Center. Dr. MacLean is recip- ient of a Veterans Affairs Health Services Research and Development Career Development award. 1 K. L. Kahn, MD: University of California, Los Angeles, and RAND, Santa Monica, California; 2 C. H. MacLean, MD, PhD: University of California, Los Angeles, and Greater Los Angeles VA Healthcare System, Los Angeles, California; 3 H. Liu, PhD, W. P. Chen, MA, D. M. Fitzpatrick, RN, S. B. Traina, PhD, B. H. Hahn, MD, H. E. Paulus, MD: University of California, Los Angeles; 4 L. Z. Rubenstein, MD, MPH: RAND, Santa Monica, and Greater Los Angeles VA Health- care System, Los Angeles, California; 5 A. L. Wong, MD: University of California, Los Angeles, Greater Los Angeles VA Healthcare System, Los Angeles, and Los Angeles Coun- ty/Olive View/University of California, Los Angeles Medical Center, Sylmar, California; 6 J. O. Harker, PhD, B. S. Mitt- man, PhD: Greater Los Angeles VA Healthcare System, Los Angeles, California; 7 K. J. Bulpitt, MD: Kaiser Permanente West Los Angeles Medical Center, Los Angeles, California. Address correspondence to K. L. Kahn, MD, University of California at Los Angeles, David Geffen School of Medicine, Division of General Internal Medicine and Health Services Research, 911 Broxton Plaza, Box 951736, Los Angeles, CA 90095-1736. E-mail: kkahn@mednet.ucla.edu. Submitted for publication February 9, 2006; accepted in revised form March 29, 2006. Arthritis & Rheumatism (Arthritis Care & Research) Vol. 55, No. 6, December 15, 2006, pp 884 – 891 DOI 10.1002/art.22361 © 2006, American College of Rheumatology ORIGINAL ARTICLE 884