Table 1.

Awareness, experience and prevalence of IQOS among the Korean young adults and multivariable association of IQOS awareness and ever use

Factor	Category	n (228)	Univariate association between IQOS awareness/ever use/current use and sociodemographic characteristic and smoking behaviour						Multivariable association of IQOS awareness and ever use
			IQOS awareness (n=87)		IQOS ever use (n=13)		Current IQOS use (n=8)		IQOS awareness	IQOS ever use
			n (%)	P values	n (%)	P values	n (%)	P values	OR (95% CI)	OR (95% CI)
Gender	Female	114	46 (52.9)	0.495	9 (69.2)	0.153	6 (75.0)	0.569	Ref	Ref
	Male	114	41 (47.1)		4 (30.8)		2 (25.0)		1.10 (0.59 to 2.05)	3.11 (0.67 to 14.30)
Age (mean±SD)		228	22.31±1.43	0.279	21.92±1.12	0.526	21.50±0.93	0.082	1.12 (0.89 to 1.40)	0.80 (0.46 to 1.37)
Education level	High school	121	27 (31.0)	0.497	4 (30.8)	0.770	2 (25.0)	0.850	Ref	Ref
	2-year college degree	37	11 (12.6)		3 (23.1)		2 (25.0)		0.70 (0.25 to 1.96)	0.84 (0.10 to 6.78)
	4-year college degree	70	49 (56.3)		6 (46.2)		4 (50.0)		1.51 (0.71 to 3.20)	1.22 (0.22 to 6.68)
Monthly allowance (KRW)	None	49	14 (16.1)	0.076	1 (7.7)	0.028	0 (0.0)	0.386	Ref	Ref
	Less than 50 000 won	39	13 (14.9)		1 (7.7)		1 (12.5)		1.65 (0.59 to 4.61)	1.72 (0.06 to 50.87)
	50 000–99 999 won	54	17 (19.5)		3 (23.1)		1 (12.5)		1.28 (0.49 to 3.29)	3.63 (0.23 to 57.01)
	100 000–149 999 won	41	20 (23.0)		1 (7.7)		1 (12.5)		1.59 (0.60 to 4.27)	0.37 (0.02 to 9.47)
	More than 150 000 won	45	23 (26.4)		7 (53.8)		5 (62.5)		1.00 (0.36 to 2.80)	1.95 (0.17 to 22.78)
Conventional cigarette smoking	Never smoker	151	37 (42.5)	0.000	1 (7.7)	0.000	0 (0.0)	0.188	Ref	Ref
	Current smoker	77	50 (57.5)		12 (92.3)		8 (100.0)		4.50** (2.19 to 9.25)	11.65* (1.02 to 132.56)
E-cigarette use	Never e-cigarette user	194	65 (71.3)	0.000	3 (23.1)	0.000	0 (0.0)	0.012	Ref	Ref
	Current e-cigarette user	34	25 (28.7)		10 (76.9)		8 (100.0)		2.99* (1.11 to 8.07)	9.65* (1.63 to 57.01)

KRW is South Korea’s currency, the won (1000 won=US$1).

*P<0.05; **P<0.0001.