Table 1

Characteristics of tobacco users

TotalType of tobacco products usedP value*
CC onlyHTP onlyEC onlyCC+HTPCC+ECHTP+ECTriple
N3294 (100.0)2652 (80.5)116 (3.5)70 (2.1)164 (5.0)212 (6.4)10 (0.3)70 (2.1)
Sex0.002
 Male2415 (73.3)1986 (74.9)73 (62.9)49 (70.0)116 (70.7)142 (67.0)6 (60.0)43 (61.4)
 Female879 (26.7)666 (25.1)43 (37.1)21 (30.0)48 (29.3)70 (33.0)4 (40.0)27 (38.6)
Age (years)<0.001
 15–29695 (21.1)461 (17.4)14 (12.1)32 (45.7)39 (23.8)113 (53.3)2 (20.0)34 (48.6)
 30–39952 (28.9)695 (26.2)61 (52.6)25 (35.7)80 (48.8)61 (28.8)5 (50.0)25 (35.7)
 40–49810 (24.6)698 (26.3)30 (25.9)9 (12.9)36 (22.0)27 (12.7)1 (10.0)9 (12.9)
 50 or more837 (25.4)798 (30.1)11 (9.5)4 (5.7)9 (5.5)11 (5.2)2 (20.0)2 (2.9)
Education<0.001
 Secondary or below1952 (59.3)1700 (64.1)48 (41.4)30 (42.9)54 (32.9)87 (41.0)6 (60.0)27 (38.6)
 Tertiary1342 (40.7)952 (35.9)68 (58.6)40 (57.1)110 (67.1)125 (59.0)4 (40.0)43 (61.4)
Marital status<0.001
 Single1260 (38.3)910 (34.3)46 (39.7)43 (61.4)78 (47.6)133 (62.7)3 (30.0)47 (67.1)
 Married1793 (54.4)1523 (57.4)64 (55.2)25 (35.7)81 (49.4)73 (34.4)6 (60.0)21 (30.0)
 Divorced/widowed241 (7.3)219 (8.3)6 (5.2)2 (2.9)5 (3.0)6 (2.8)1 (10.0)2 (2.9)
Household income (HK$)<0.001
 <20 000580 (18.6)515 (20.5)8 (7.1)4 (6.2)14 (8.9)31 (15.6)2 (20.0)6 (9.2)
 20 000–39 9991190 (38.1)975 (38.8)46 (40.7)22 (33.8)51 (32.5)69 (34.7)2 (20.0)25 (38.5)
 ≥40 0001350 (43.3)1021 (40.7)59 (52.2)39 (60.0)92 (58.6)99 (49.7)6 (60.0)34 (52.3)
Exhaled carbon monoxide levels (ppm)†<0.001
 Sample size (n)78049170159760740
 Median (25th, 75th centiles)14.0 (6.0, 22.0)18.0 (12.0, 26.0)3.5 (2.8, 5.0)3.0 (2.0, 3.0)6.0 (3.0, 15.0)11.0 (5.3, 17.0)4.0 (2.0, 5.0)8.5 (3.3, 18.5)
Saliva cotinine level‡0.81
 Sample size (n)6204264486850420
 Median (25th, 75th centiles)3.0 (2.0, 4.0)3.0 (3.0, 4.0)3.0 (2.0, 4.0)3.5 (2.3, 4.0)4.0 (2.0, 4.0)3.5 (2.0, 4.0)4.0 (1.8, 4.8)4.0 (2.0, 4.0)
  • US$1=HK$7.8.

  • *P value was based on χ2 test.

  • †The exhaled carbon monoxide levels are expressed in ppm, with 0–6 ppm indicating no smoking and >6 ppm suggesting smoking (7–9 ppm: borderline; 10–15 ppm: mild addiction; 16–25 ppm: moderate addiction; 26+ ppm: heavy addiction).

  • ‡The saliva cotinine levels of 0–6 correspond to saliva cotinine concentrations of 0–10 (indicating non-users of tobacco products), 10–30, 30–100, 100–200, 200–500, 500–1000 and 1000+ ng/mL, respectively.

  • CC, conventional cigarette; EC, electronic cigarette; HTP, heated tobacco product.