Choi HS, et al. - In this phase 3, randomized, controlled study, researchers tested the Exacerbations of Chronic Obstructive Pulmonary Disease Tool-Patient-Reported Outcomes (EXACT-PRO) with respect to its reliability, validity, and responsiveness for the assessment of the efficacy of acute treatment in patients with COPD exacerbation. This study included 259 responders and 37 non-responders. For EXACT total, for the breathlessness domain, and for the cough and sputum domain, Cronbach’s α was 0.96, 0.96, and 0.89, respectively. Cronbach’s α was 0.93 for the chest symptoms domain. A correlation of EXACT score with the COPD assessment test (CAT) score was also seen. From the fifth day post-treatment, the responder group vs the non-responder group exhibited a stronger decrease in the EXACT score. Overall, EXACT-PRO constitutes a comprehensive and sensitive tool for evaluating symptomatic resolution of COPD exacerbations during treatment.