The Validity and Reliability of the Turkish version of Modified Medical Research Council Dyspnea Scale in Systemic Sclerosis Patients with Interstitial Lung Disease

Abstract

OBJECTIVE: The aim was to investigate the validity and reliability of the Turkish version of the Modified Medical Research Council (mMRC) Dyspnea Scale in Systemic Sclerosis (SSc) patients with Interstitial Lung Disease. MATERIAL AND METHODS: Thirty patients diagnosed with SSc according to the 2013 EULAR/ACR criteria were included. After recording the demographic data of the patients, dyspnea was evaluated with the Visual Analogue Scale (VAS), exercise capacity with the 6 Minute Walk Distance (6MWD), fatigue level with the Fatigue Severity Scale (FSS), disease activity with the Medsger Disease Severity Scale, skin involvement with the Modified Rodnan Skin Score, and dyspnea level with the mMRC Dyspnea Scale. The mMRC Dyspnea Scale was administered to the patients with SSc who did not receive any treatment for test-retest reliability at 1-week intervals. RESULTS: The observed scale range in mMRC (TR) was 0-4, and twelve out of the thirty patients (40%) were classified as having "moderate dyspnea." mMRC (TR) showed a significant moderate positive correlation with VAS dyspnea (rho: 0.718), a low negative correlation with 6MWD (rho: -0.445), and a low positive correlation with FSS (rho: 0.385). The weighted kappa statistic, used as an agreement scale for ordinal responses, was found to be 0.587 (indicating moderate agreement). CONCLUSION: The Turkish version of the mMRC Dyspnea Scale demonstrates validity and reliability in SSc patients with interstitial lung disease.