Chronic obstructive pulmonary disease (COPD) patients can significantly benefit from their COPD Exacerbation Recognition Tool (CERT) to know when to seek medical attention following exacerbations, suggests a research. The research conducted by a team of medical experts and scientists from different hospitals in China was run across three sites in China in patients who had exacerbations in the previous year. The researchers said that mainly five items were selected for the CERT analysis based on response rate and EFA factor loading; worsening cough, increased sputum volume, shortness of breath, laborious breathing, and limitation of motion. The findings indicated that worsening of two or more symptoms had good sensitivity and specificity for the presence of an exacerbation, and thus CERT was effective in providing patients with  simple-to-follow guidance about when to seek medical attention when their COPD symptoms might worsen.