Table 7.

—Sensitivity, Specificity, and Positive and Negative Predictive Values of Symptoms for Airway Obstruction

	All Subjects (N = 3,955)				Smokers ≥ 20 Pack-y (n = 2,917)
Symptom	Sensitivity	Specificity	PPV	NPV	Sensitivity	Specificity	PPV	NPV
Cough	69	48	43	72	71	44	49	66
Dyspnea	75	37	41	72	76	37	48	67
Sputum	56	60	48	68	57	61	53	65
Wheeze	68	55	47	75	70	49	52	68
≥ 1 symptom	90	22	40	80	92	19	47	75
Smoking ≥ 20 pack-y	88	34	43	83	…	…	…	…

NPV = negative predictive value; PPV = positive predictive value.