Kerkhof M, Freeman D, Jones R, Chisholm A, Price DB. Int J Chron Obstruct Pulmon Dis. 2015;10:2439–2450.Page 2450, the formula shown in the Supplementary materials is incorrect. The correct formula is shown below. The formula: Risk of ≥2 COPD exacerbations within the next 12 months =1/{1 + exp[- (-0.7306 + 0.8840 × 1 previous exacerbation in last 12 months + 1.4786 × 2 previous exacerbations in last 12 months + 1.9857 × 3 previous exacerbations in last 12 months + 2.8811 × ≥4 previous exacerbations in last 12 months - 0.0093 × FEV1% predicted + 0.0360 × age - 0.0004 × age2 - 1.2194 × height (in meter) + 0.2518 × (blood eosinophil count ≥400/μL in a patient who is not currently smoking) + 0.2953 × any evidence of asthma × 0.3018 × history of non allergic rhinitis + 0.3298 × history of nasal polyps + 0.1164 × history of ischemic heart disease + 0.1071 × history of anxiety or depression + 0.1689 × history of GERD)]}. For the yes/no variables, a value of 1 should be used for “yes” and a value of 0 for “no.”Read the original article.
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