Validity of a questionnaire-based diagnosis of chronic obstructive pulmonary disease in a general population-based study

Table 5 Diagnostic accuracy of self-reported, questionnaire-based chronic bronchitis symptoms to detect chronic obstructive pulmonary disease (COPD), in non-smokers, ex-smokers, and current smokers

		FEV₁/FVC <0.7 (GOLD)		FEV₁/FVC <1.645 SD below predicted (ATS/ERS)
		Value	95% CI	Value	95% CI
Sensitivity	Non-smokers	0.044	−0.004–0.092	0.044	−0.032–0.121
	Ex-smokers	0.042	0–0.084	0.094	0.003–0.185
	Current smokers	0.052	0–0.104	0.067	−0.014–0.147
Specificity	Non-smokers	0.981	0.973–0.989	0.980	0.971–0.988
	Former smokers	0.979	0.968–0.989	0.980	0.970–0.990
	Current smokers	0.977	0.960–0.993	0.975	0.959–0.992
PPV	Non-smokers	0.128	−0.006–0.262	0.051	−0.037–0.14
	Former smokers	0.182	0.014–0.35	0.182	0.014–0.35
	Current smokers	0.333	0.056–0.611	0.222	−0.023–0.467
NPV	Non-smokers	0.943	0.929–0.956	0.976	0.967–0.985
	Former smokers	0.901	0.881–0.921	0.962	0.949–0.975
	Current smokers	0.821	0.783–0.86	0.908	0.879–0.937

ATS = American Thoracic Society; CI = confidence interval; ERS = European Respiratory Society; FEV₁ = forced expiratory volume in 1 second; FEV₁/FVC = FEV₁/forced vital capacity ratio; Gold = Global Initiative for Chronic Obstructive Lung Disease; NPV = negative predictive value; PPV = positive predictive value.

ISSN: 1471-2466