Table 1

Patient characteristics, symptoms and their duration

Subject no.	Sex	Age yrs	Smoking	Pack-yrs	Years since quitting	Cough	Cough Duration months	Sputum	Sputum Duration months	Dyspnoea	Dyspnoea Duration months	Wheeze	Wheeze Duration months	Other	Asthma Diagnosis
1	M	57	FS	7	19					+	31
2	F	21	NS			+	2			+	0.25
3	F	45	NS			+	9	+	7	+	9				+
4	F	50	FS	14	3	+	84	+	84	+	48	+	84
5	F	51	CS	20		+	4			+	4	+	4		+
6	F	36	NS			+	24			+	24
7	F	44	CS	22		+	2	+		+	72				+
8	M	38	CS	6		+	10			+	10	+	10
9	F	38	NS			+	15	+	15	+	15	+	15		+
10	F	58	FS	2.5	32					+	12
11	M	50	FS	60	2					+	60
12	F	52	NS			+	12			+	12
13	M	36	FS	16	4	+	0.5			+	7
14	F	57	NS			+	24							#
15	M	34	NS			+	4			+	4	+	4
16	F	62	NS			+	6	+	4	+	6
17	F	44	NS			+	12	+	12	+	16	+	12	##
18	F	35	NS			+	288	+	60	+	60	+	60	*	+
19	F	55	FS	20	8					+	72	+	12	**	+

M: male
F: female
FS: former smoker
NS: never-smoker
CS: current smoker
+: positive for given symptom