ABSTRACT Background and Objective Acute exacerbations of COPD (AECOPD) worsen outcomes, yet they are often underreported. The 14‐item EXACT diary has been validated for trial use—the five‐item CERT checklist is patient‐centered. We compared the two tools' accuracy and early‐warning performance for AECOPD. Methods This prospective study examined 63 COPD patients who completed EXACT and CERT daily. Two metrics were used for CERT: total score and binary (positive if ≥ 2 items were rated as moderate/severe). AECOPD patients were bootstrap matched to a non‐exacerbator. Linear mixed‐effects models assessed score differences on the day of AECOPD diagnosis and the previous days. Results Twelve patients developed clinically confirmed AECOPD. On the day of AECOPD diagnosis, all tools discriminated AECOPD (AUC: EXACT 0.90, CERT total score 0.88, and CERT binary 0.87; p < 0.01). At optimal thresholds, sensitivities ranged from 81% to 87%, and specificities ranged from 93% to 95%. One day before the AECOPD diagnosis, the CERT total score (5.9 vs. 1.4; p = 0.006) and the CERT binary outcome (70.4% vs. 9.3%; p = 0.009) significantly distinguished impending exacerbations. However, the EXACT score did not (39.6% vs. 34.3%; p = 0.186). The CERT total score yielded an AUC of 0.86 (sensitivity 83%, specificity 86%), and the binary rating achieved a specificity of 91% and a sensitivity of 70% one day before diagnosis. Conclusion Both EXACT and CERT can accurately detect AECOPD at the time of diagnosis. However, patients were able to recognise worsening symptoms one day before an AECOPD diagnosis when using the CERT. Trial Registration clinicaltrials.gov (NCT04140097)
Jones et al. (2025) studied this question.