PMID- 25956020 OWN - NLM STAT- MEDLINE DCOM- 20160308 LR - 20150613 IS - 1532-3064 (Electronic) IS - 0954-6111 (Linking) VI - 109 IP - 7 DP - 2015 Jul TI - Validation of test performance characteristics and minimal clinically important difference of the 6-minute walk test in patients with idiopathic pulmonary fibrosis. PG - 914-22 LID - S0954-6111(15)00119-5 [pii] LID - 10.1016/j.rmed.2015.04.008 [doi] AB - BACKGROUND: The 6-minute walk test distance (6MWD) has been shown to be a valid and responsive outcome measure in patients with idiopathic pulmonary fibrosis (IPF). The analyses were based, however, on a single phase 3 trial and require validation in an independent cohort. OBJECTIVE: To confirm the performance characteristics and estimates of minimal clinically important difference (MCID) of 6MWD in an independent cohort of patients with IPF. METHODS: Patients randomized to placebo in the phase 3 CAPACITY trials who had a baseline 6MWD measurement were included in these analyses. The 6MWD and other functional parameters (lung function, dyspnea, and health-related quality of life) were measured at baseline and 24-week intervals. Validity and responsiveness were examined using Spearman correlation coefficients. The MCID was estimated using distribution- and anchor-based methods. RESULTS: The analysis comprised 338 patients. Baseline 6MWD was significantly correlated with lung function measures, patient-reported outcomes, and quality-of-life measures (validity). Compared with baseline 6MWD, change in 6MWD (responsiveness) showed stronger correlations with change in lung function parameters and quality-of-life measures. Dyspnea measured by the University of California San Diego Shortness of Breath Questionnaire showed the strongest correlations with 6MWD (baseline: coefficient -0.35; 48-week change: coefficient -0.37; both p < 0.001). The distribution-based analyses of MCID using standard error of measurement yielded an MCID of 37 m, and distribution-based analyses by effect size resulted in 29.2 m. The MCID by anchor-based analysis using criterion referencing (health events of hospitalization or death) was 21.7 m. CONCLUSIONS: The 6MWD is a valid and responsive clinical endpoint, which provides objective and clinically meaningful information regarding functional status and near-term prognosis. These results confirm previous findings in an independent cohort of patients with IPF. CI - Copyright (c) 2015 The Authors. Published by Elsevier Ltd.. All rights reserved. FAU - Nathan, Steven D AU - Nathan SD AD - Inova Fairfax Hospital, 3300 Gallows Rd., Falls Church, VA 22042, USA. Electronic address: steven.nathan@inova.org. FAU - du Bois, Roland M AU - du Bois RM AD - Imperial College, South Kensington Campus, London SW7 2AZ, UK. Electronic address: ron@du-bois.co.uk. FAU - Albera, Carlo AU - Albera C AD - University of Turin, San Luigi Gonzaga Medical School, Regione Gonzole, 1010043 Orbassano, Turin, Italy. Electronic address: carlo.albera@yahoo.it. FAU - Bradford, Williamson Z AU - Bradford WZ AD - InterMune, Inc., 3280 Bayshore Blvd., Brisbane, CA 94005, USA. Electronic address: bbradford@intermune.com. FAU - Costabel, Ulrich AU - Costabel U AD - Ruhrlandklinik, University Hospital, University of Duisburg-Essen, 45117 Essen, Germany. Electronic address: ulrich.costabel@ruhrlandklinik.uk-essen.de. FAU - Kartashov, Alex AU - Kartashov A AD - Policy Analysis Inc. (PAI), 4 Davis Ct., Brookline, MA 02445, USA. Electronic address: akartashov@pai2.com. FAU - Noble, Paul W AU - Noble PW AD - Duke University School of Medicine, 106 Research Dr., Durham, NC 27710, USA. Electronic address: paul.noble@cshs.org. FAU - Sahn, Steven A AU - Sahn SA AD - Medical University of South Carolina, 96 Jonathan Lucas St., Charleston, SC 29425, USA. Electronic address: sahnsa@musc.edu. FAU - Valeyre, Dominique AU - Valeyre D AD - Assistance Publique-Hopitaux de Paris, 3, Ave. Victoria, 75004 Paris, France. Electronic address: dominique.valeyre@avc.aphp.fr. FAU - Weycker, Derek AU - Weycker D AD - Policy Analysis Inc. (PAI), 4 Davis Ct., Brookline, MA 02445, USA. Electronic address: dweycker@pai2.com. FAU - King, Talmadge E Jr AU - King TE Jr AD - University of California, San Francisco, 505 Parnassus Ave., Box 0120, San Francisco, CA 94143, USA. Electronic address: tking@medicine.ucsf.edu. LA - eng PT - Clinical Trial, Phase III PT - Journal Article PT - Multicenter Study PT - Randomized Controlled Trial PT - Research Support, Non-U.S. Gov't DEP - 20150424 PL - England TA - Respir Med JT - Respiratory medicine JID - 8908438 RN - 0 (Anti-Inflammatory Agents, Non-Steroidal) RN - 0 (Pyridones) RN - 0 (Tumor Necrosis Factor-alpha) RN - D7NLD2JX7U (pirfenidone) SB - IM MH - Adult MH - Aged MH - Aged, 80 and over MH - Anti-Inflammatory Agents, Non-Steroidal/therapeutic use MH - Exercise Test/*methods MH - Female MH - Follow-Up Studies MH - Humans MH - Idiopathic Pulmonary Fibrosis/*diagnosis/drug therapy/physiopathology MH - Male MH - Middle Aged MH - Prognosis MH - Pyridones/therapeutic use MH - *Quality of Life MH - Surveys and Questionnaires MH - Time Factors MH - Tumor Necrosis Factor-alpha/antagonists & inhibitors MH - Walking/*physiology OTO - NOTNLM OT - 6-minute walk test OT - Dyspnea OT - Idiopathic pulmonary fibrosis OT - Lung function OT - Minimal clinically important difference EDAT- 2015/05/10 06:00 MHDA- 2016/03/10 06:00 CRDT- 2015/05/10 06:00 PHST- 2014/12/05 00:00 [received] PHST- 2015/04/10 00:00 [revised] PHST- 2015/04/13 00:00 [accepted] PHST- 2015/05/10 06:00 [entrez] PHST- 2015/05/10 06:00 [pubmed] PHST- 2016/03/10 06:00 [medline] AID - S0954-6111(15)00119-5 [pii] AID - 10.1016/j.rmed.2015.04.008 [doi] PST - ppublish SO - Respir Med. 2015 Jul;109(7):914-22. doi: 10.1016/j.rmed.2015.04.008. Epub 2015 Apr 24.