Laryngeal Measurements and Diagnostic Tools for Diagnosis of Chronic Obstructive Pulmonary Disease

PURPOSE The purpose of this study was to evaluate sensitivity, specificity, and positive and negative likelihood ratios of laryngeal height, lung function, and diagnostic questionnaires for screening and diagnosis of chronic obstructive pul- monary disease (COPD). METHODS We undertook a cross-sectional study of 233 people aged between 40 and 75 years. Measured variables were age, sex, weight, height, body mass index, tobacco use, maximum laryngeal height, and spirometry, and we adminis- tered a COPD questionnaire and the Lung Function Questionnaire. RESULTS For laryngeal height, we found a positive likelihood ratio of 5.21, and for the Lung Function Questionnaire, we found a negative likelihood ratio of 0.10. Combining a maximum laryngeal height of ≤4 cm with Lung Function Questionnaire findings of ≤18 yielded a positive likelihood ratio of 29.06, and a negative likelihood ratio of 0.26. CONCLUSIONS The intrinsic validity of the lung function questionnaire makes it useful for screening. Combining Lung Function Questionnaire results and laryn- geal height can help confirm or dismiss COPD.