ORIGINAL RESEARCH Qualitative Research with Patients and Physicians to Assess Content Validity and Meaningful Change on ESSDAI and ESSPRI in Sjo ¨gren’s Carl Cooper . Samantha Wratten . Rebecca Williams-Hall . Arthur A. M. Bookman . Briana Ndife . Wolfgang Hueber . Pushpendra Goswami Received: July 27, 2022 / Accepted: August 17, 2022 Ó The Author(s) 2022 ABSTRACT Introduction: European Alliance of Associa- tions for Rheumatology (EULAR) Sjo ¨gren’s Syndrome Disease Activity Index (ESSDAI) is a clinician-reported outcome (ClinRO) instru- ment, assessing Sjo ¨gren’s disease activity from the physician perspective. EULAR Sjo ¨gren’s Syndrome Patient Reported Index (ESSPRI) is a patient-reported outcome (PRO) instrument, assessing patient-defined Sjo ¨gren’s symptom severity. Both instruments are commonly used as clinical trial endpoints and have been psy- chometrically validated. However, qualitative evidence supporting content validity and what constitutes a meaningful change is limited. Qualitative evidence supporting Physician/ Patient Global Assessment of disease activity and symptom severity (PhGA/PaGA) items used within anchor-based analyses for ESSDAI/ ESSPRI is also lacking. Methods: Qualitative, semi-structured, tele- phone/video interviews were conducted with patients with Sjo ¨gren’s (n = 12) and physicians who specialise in Sjo ¨gren’s (n = 10). Interviews explored: appropriateness of ESSDAI domain weights and meaningful improvements on domain/total scores from the physician per- spective, appropriateness of ESSPRI’s 2-week recall period from the patient/physician per- spective, patients’ perspectives on meaningful improvements in ESSPRI total scores, and patients’/physicians’ interpretation of PhGA/ PaGA items. Results: Most ESSDAI domain weights were considered clinically appropriate. Generally, a one-category improvement in domain-level scores and a 3-point improvement in total ESS- DAI scores were considered clinically meaning- ful. Most patients/physicians considered ESSPRI’s 2-week recall period appropriate, and patients considered a 1-to-2-point ESSPRI total score improvement meaningful. PhGA/PaGA items developed for use as ESSDAI/ESSPRI anchors were consistently interpreted. Conclusions: The findings support use of ESS- DAI and ESSPRI as Sjo ¨gren’s clinical trials end- points, as well as in clinical practice and other research settings. Qualitative data exploring meaningful change supports existing minimal C. Cooper Á S. Wratten Á R. Williams-Hall Patient-Centered Outcomes, Adelphi Values, Bollington, Cheshire, UK A. A. M. Bookman Division of Rheumatology, Toronto Western Hospital/UHN, University of Toronto, Toronto, ON, Canada B. Ndife Department of US Oncology HEOR, Novartis Pharmaceuticals Corporation, East Hanover, New Jersey, USA W. Hueber Á P. Goswami (&) Novartis Pharma AG, Fabrikstrasse 2, 4056 Basel, Switzerland e-mail: pushpendra.goswami@novartis.com Rheumatol Ther https://doi.org/10.1007/s40744-022-00487-0