TY - JOUR T1 - An updated approach to determine minimal clinically important differences in idiopathic pulmonary fibrosis JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00142-2021 VL - 7 IS - 4 SP - 00142-2021 AU - Mohleen Kang AU - Srihari Veeraraghavan AU - Greg S. Martin AU - Jordan A. Kempker Y1 - 2021/10/01 UR - http://openres.ersjournals.com/content/7/4/00142-2021.abstract N2 - Introduction Current medications for idiopathic pulmonary fibrosis (IPF) have not been shown to impact patient-reported outcome measures (PROMs), highlighting the need for accurate minimal clinically important difference (MCID) values. Recently published consensus standards for MCID studies support using anchor-based over distribution-based methods. The aim of this study was to estimate MCID values for worsening in IPF using only an anchor-based approach.Methods We conducted secondary analyses of three randomised controlled trials with different inclusion criteria and follow-up intervals. The health transition question in the 36-Item Short-Form Health Survey (SF-36) questionnaire was used as the anchor. We used receiver operating curves to assess responsiveness between the anchor and 10 variables (four physiological measures and six PROMs). We used an anchor-based method to determine the MCID values of variables that met the responsiveness criteria (area under the curve ≥0.70).Results 6-min walk distance (6MWD), the St George's Respiratory Questionnaire (SGRQ), physical component score (PCS) of SF-36 and University of California, San Diego, Shortness of Breath Questionnaire (UCSD SOBQ) met the responsiveness criteria. The MCID value for 6MWD was −75 m; the MCID value for SF-36 PCS was −7 points; the MCID value for SGRQ was 11 points; and the MCID value for the UCSD SOBQ was 11 points.Conclusions The MCID estimates of 6MWD, SGRQ, SF-36 and UCSD SOBQ using only anchor-based methods were considerably higher compared to previously proposed values. A single MCID value may not be applicable across all classes of disease severity or durations of follow-up time.Current consensus approaches recommend anchor-based estimation of MCID over distribution-based methods. MCID values of 6MWD, SGRQ, SF-36 and UCSD SOBQ using only anchor-based method were higher than previously reported values. https://bit.ly/37hm0zv ER -