Table 2. Smoking status of patients with chronic cough.

Smoking status	20–49 years			50–89 years			Total
	Female	Male	All	Female	Male	All
Never smokers	568 (31.2)	522 (28.6)	1,090 (59.8)	360 (19.8)	133 (7.3)	493 (27.1)	1,583 (86.9)
Former smokers	4 (0.2)	91 (5.0)	95 (5.2)	1 (0.1)	60 (3.3)	61 (3.4)	156 (8.6)
Current smokers	6 (0.3)	62 (3.4)	68 (3.7)	0 (0.0)	15 (0.8)	15 (0.8)	83 (4.5)

Data are presented as number (%). Patients who had no smoking history were defined as never smokers, those with a smoking history who had quit smoking for more than 1 month were defined as former smokers, otherwise they were defined as current smokers.