Validity of questionnaires in screening chronic obstructive pulmonary disease in communities of Shanghai

ObjectiveTo evaluate the validity of four screening questionnaires on chronic obstructive pulmonary disease (COPD) among community residents in Shanghai, and to provide a scientific basis for selecting suitable screening questionnaires and plans for the community use.MethodsA multi-stage random sampling method was used to select community residents aged ≥40 for COPD questionnaire screening and spirometry. The screening questionnaires included the COPD Population Screener Questionnaire (COPD-PS), the COPD Screening Questionnaire (COPD-SQ), the COPD Diagnosis Questionnaire (CDQ), and the Lung Function Questionnaire (LFQ). The diagnostic gold standard for COPD was defined as a ratio of post-bronchodilator forced expiratory volume in one second to forced vital capacity (FEV1/FVC) less than 0.7. The receiver operating characteristic (ROC) curve was used to assess the validity of each questionnaire, and DeLong’s test was used to compare the area under the curve (AUC) of different questionnaires.ResultsAmong the 1 122 residents screened, 99 (8.8%) were diagnosed with COPD based on the gold standard criteria. The AUC values for the four questionnaires ranged from 0.643 to 0.682, with no statistically significant differences in screening accuracy among them (P>0.05). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each questionnaire at recommended cut-off points were as follows: COPD-PS (sensitivity: 33.3%, specificity: 84.9%, PPV: 17.6%, NPV: 92.9%), COPD-SQ (34.3%, 85.8%, 19.0%, 93.1%), CDQ (73.7%, 42.4%, 11.0%, 94.4%), and LFQ (48.5%, 74.8%, 15.7%, 93.8%). Optimal cut-off values for this population differed from the recommended values. When selecting the optimal cut-off value, the sensitivity of COPD-PS (58.6%), COPD-SQ (55.6%), and LFQ (64.7%) increased, while the specificity of CDQ (75.9%) increased. The AUC of sequential lung function testing for all four screening questionnaires increased to 0.7 or above. The optimal cut-off values for the four questionnaires in this population differed from the recommended values. When applying the optimal cut-off values, the sensitivity of three questionnaires increased: COPD-PS (58.6%), COPD-SQ (55.6%), and LFQ (64.7%), while the specificity of CDQ rose to 75.9%. The AUC of each questionnaire increased to above 0.7 when followed by sequential lung function testing.ConclusionThe COPD-PS, COPD-SQ, CDQ, and LFQ have limited value for COPD screening among Shanghai community residents, indicating that further refinement of these tools is needed.