Table 1

Sample characteristics at recruitment in China and Malaysia

		China (n=6575)		Malaysia (n=2883)
Variable	Value	Freq	Per cent	Freq	Per cent
City (China only)	Beijing	961	14.6	–	–
	Shenyang	1257	19.1	–	–
	Shanghai	968	14.7	–	–
	Changsha	1037	15.8	–	–
	Guangzhou	1197	18.2	–	–
	Yinchuan	1155	17.6	–	–
Cohort	Recruited in Wave 1	4795	72.9	939	32.6
	Recruited in Wave 2	920	14.0	438	15.2
	Recruited in Wave 3	860	13.1	749	26.0
	Recruited in Wave 4	–	–	757	26.3
Sex	Male	6221	94.6	2847	98.8
Sex	Female	354	5.4	36	1.2
Age group	18–24	91	1.4	914	31.7
	25–39	1134	17.2	919	31.9
	40–54	3167	48.2	701	24.3
	55+	2183	33.2	309	10.7
	Not stated	–	–	40	1.4
Income	Low	1227	18.7	766	26.6
	Medium	2888	43.9	806	28.0
	High	1969	29.9	749	26.0
	Not stated	491	7.5	562	19.5
Education	Low	839	12.8	390	13.5
	Medium	4282	65.1	2188	75.9
	High	1431	21.8	244	8.5
	Not stated	23	0.3	61	2.1
Smoking status	Daily	6152	93.6	2704	93.8
Smoking status	Weekly	423	6.4	179	6.2
Cigarettes per day	0–10 cigs	2379	36.2	1360	47.2
	11–20 cigs	3177	48.3	1270	44.1
	21–30 cigs	528	8.0	124	4.3
	31+ cigs	454	6.9	57	2.0
	Not stated	37	0.6	72	2.5
Time to first cigarette	61+ min	1738	26.4	551	19.1
	31–60 min	941	14.3	634	22.0
	6–30 min	1631	24.8	733	25.4
	≤5 min	1805	27.5	512	17.8
	Not stated	460	7.0	453	15.7
Intention to quit	Yes	1020	15.5	393	13.6
	No	4867	74.0	2277	79.0
	Not stated	688	10.5	213	7.4