Do symptom-based questions help screen COPD among Chinese populations?

Spirometry is required to confirm a chronic obstructive pulmonary disease (COPD) diagnosis, but it is difficult to perform in resource-limited settings. This study aimed to evaluate symptom-based questions for screening of individuals with COPD among Chinese populations. We recruited 3969 adult subjects from the First Affiliated Hospital of Nanjing Medical University. Spirometric measurements of forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were collected to confirm the COPD diagnosis. A symptom-based questionnaire was administered to collect data related to COPD. The sensitivity and specificity together with the area under the curve (AUC) were calculated. The traditional IPAG eight-item questionnaire yielded an AUC of 0.80(95% CI: 0.78-0.82), with a sensitivity of 67.8% and specificity of 76.8%. After removing and adding questions, a revised eleven-item questionnaire exhibited a significantly increased diagnostic accuracy, with an AUC of 0.85(95% CI: 0.84-0.87). At the inflection point of the curve, it demonstrated a sensitivity of 82.5% and specificity of 72.9%. We showed that the revised symptom-based questionnaire could be used to screen individuals with a high likelihood of COPD among Chinese populations. Further validation is required before we claim it is a useful diagnostic for primary care populations.