From: Systematic review of the relation between smokeless tobacco and cancer in Europe and North America
 | ST use |  |  | RR/OR | ||||
---|---|---|---|---|---|---|---|---|
Sourcea | Typeb | Exposurec | Smoking | Sex | Id. | Casesd | Estimate (95%CI)e | Adjustment factorsf |
Cohort studies | Â | Â | Â | Â | Â | Â | Â | Â |
US Veterans: Winn et al. 1982 [19] | ST | Ever | Never | Mg | 1 | NA | 0.60 (NA) | age |
NHANES I: Accortt et al. 2005 [22] | ST | Ever | Never | F | 2 | 4 | 6.80 (1.60–28.5) | age, pov, race |
CPS-I: Henley et al. 2005 [23] | ST | Current | Never | M | 3 | 18 | 1.08 (0.64–1.83) | age, alc, asp, bmi, diet, edu, exer, occ, race |
CPS-II: Henley et al. 2005 [23] | ST | Current | Never | M | 4 | 18 | 2.00 (1.23–3.24) | age, alc, asp, bmi, diet, edu, exer, occ, race |
 | ST | Former |  |  | 5 | 4 | 1.17 (0.43–3.14) |  |
 | ST | Ever |  |  | 6 | 22 | 1.77 (1.14–2.74)h |  |
 | Chew only | Current |  |  | 7 | 12 | 1.97 (1.10–3.54) |  |
 | Snuff only |  |  |  | 8 | 2 | 2.08 (0.51–8.46) |  |
Norway cohorts: Boffetta et al. 2005 [26] | Snuff | Current | Any | M | 9 | 44 | 0.80 (0.58–1.11) | age, smok |
 |  | Former |  |  | 10 | 28 | 0.80 (0.54–1.19) |  |
 |  | Ever |  |  | 11 | 72 | 0.80 (0.61–1.05) |  |
 |  | Ever | Never |  | 12 | 3 | 0.96 (0.26–3.56) | age |
Swedish construction workers: Luo et al. 2007 [32] | Snuff | Ever | Any | M | 13 | NA | 0.70 (0.60–0.70) | age, bmi, smok |
 |  | Current | Never |  | 14 | 15 | 0.80 (0.40–1.30) | age, bmi |
 |  | Former |  |  | 15 | 3 | 0.90 (0.30–3.00) |  |
 |  | Ever |  |  | 16 | 18 | 0.80 (0.50–1.30) |  |
Case-control studies | Â | Â | Â | Â | Â | Â | Â | Â |
Doll and Hill 1952 [38] | Chew | Ever | Any | M | 17 | 40 | 0.61 (0.41–0.92)h | none |
 | Snuff |  |  |  | 18 | 33 | 0.76 (0.48–1.21)h |  |
 | ST |  |  |  | 19 | 73 | 0.66 (0.41–0.90)h |  |
Williams and Horm 1977 [55] | ST | Ever | Any | M | 20 | 36 | 0.69 (0.47–1.00)h | age, race, smok |
 |  |  |  | F | 21 | 1 | 0.38 (0.05–2.80)h | none |
Wynder and Stellman 1977 [56] | Chew | Ever | Any | M | 22 | 117 | 1.26 (0.99–1.59)h | none |
 | Snuff |  |  |  | 23 | 35 | 1.25 (0.83–1.89)h |  |
 | ST |  |  |  | 24 | 152 | 1.27 (1.03–1.57)h |  |