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) | Adjustment factorse |
Cohort studies | Â | Â | Â | Â | Â | Â | Â | Â |
US Veterans: Zahm et al. 1992 [17] | ST | Ever | Any | Mf | 1 | 129 | 4.11 (2.90–5.84)g | age, time |
CPS-I: Henley et al. 2005 [23] | ST | Current | Never | M | 2 | 4 | 2.02 (0.53–7.74) | age, alc, asp, bmi, diet, edu, exer, occ, race |
CPS-II: Henley et al. 2005 [23] | ST | Current | Never | M | 3 | 1 | 0.90 (0.12–6.71) | age, alc, asp, bmi, diet, edu, exer, occ, race |
Norway Cohorts: Boffetta et al. 2005 [26] | Snuff | Current | Any | M | 4 | 6 | 1.13 (0.45–2.83) | age, smok |
 |  | Former |  |  | 5 | 3 | 1.04 (0.31–3.50) |  |
 |  | Ever |  |  | 6 | 9 | 1.10 (0.50–2.41) |  |
Swedish construction workers: Luo et al. 2007 [32] | Snuff | Ever | Any | M | 7 | NA | 0.70 (0.50–0.90) | age, bmi, smok |
 |  | Current | Never |  | 8 | 9 | 0.90 (0.40–1.80) | age, bmi |
 |  | Former |  |  | 9 | 1 | 0.70 (0.10–5.00) |  |
 |  | Ever |  |  | 10 | 10 | 0.80 (0.40–1.70) |  |
Uppsala County: Roosaar et al. 2008 [35] | Snuff | Ever | Any | M | 11 | 11 | 3.10 (1.50–6.60) | age, alc, res, smok, time |
 |  |  | Never |  | 12 | 5 | 2.30 (0.70–8.30) | age, alc, res, time |
Case-control studies | Â | Â | Â | Â | Â | Â | Â | Â |
Broders 1920 [37] | Chew | Use | Any | M+F | 13 | 128 | 2.05 (1.48–2.83)g | smok |
 | Snuff |  |  |  | 14 | 2 | 1.76 (0.12–26.52)g | none |
 | ST |  |  |  | 15 | 130 | 2.05 (1.48–2.83)g |  |
Moore et al. 1953 [39] | ST | Use | Any | M | 16 | 65 | 3.00 (1.37–6.54)g | none |
Wynder et al. 1957 [40] | Chew | Ever | Any | M | 17 | NA | no associationh | none |
Wynder and Bross 1957 [41] | Chew | Ever | Any | M | 18 | 91 | 2.00 (1.16–3.47)g | smok |
Peacock et al. 1960 [42] | ST | Use | Any | M | 19 | 14 | 3.06 (1.08–8.63)g | age, ins |
 |  |  |  | F | 20 | 11 | 2.00 (0.66–6.01)g |  |
Vogler et al. 1962 [36] | Chew | Ever | Any | M | 21 | 46 | 7.38 (4.31–12.62)g | none |
 | Snuff |  |  | F | 22 | 54 | 38.28 (21.49–68.15)g |  |
Vincent and Marchetta 1963 [45] | Snuff | Use | Any | M | 23 | 12 | 4.22 (1.41–12.63)g | none |
Martinez et al. 1969 [49] | Chew | Use | Any | M | 24 | 4 | 2.29 (0.62–8.48)g | none |
 |  |  |  | F | 25 | 1 | 0.34 (0.04–2.79)g |  |
Keller 1970 [50] | ST | Use | Any | M | 26 | 11 | 3.63 (1.02–12.95)g | smok |
 |  |  | Never |  | 27 | 4 | 3.04 (0.62–14.99)g |  |
Browne et al. 1977 [54] | Chew | Use | Any | M+F | 28 | 7 | 0.67 (0.27–1.66)g | none |
Williams and Horm 1977 [55] | ST | Ever | Any | M | 29 | 16 | 0.91 (0.53–1.56)g | none |
 |  |  |  | F | 30 | 2 | 1.54 (0.37–6.42)g |  |
Wynder and Stellman 1977 [56] | Chew | Ever | Any | M | 31 | 10 | 0.62 (0.32–1.21)g | none |
 | Snuff |  |  |  | 32 | 61 | 1.15 (0.85–1.55)g |  |
 | ST |  |  |  | 33 | 71 | 1.02 (0.78–1.34)i |  |
Westbrook et al. 1980 [59] | Snuff | Ever | Any | F | 34 | 50 | 540.00 (60.97–4782.82)g | none |
Winn et al. 1981 [61] | Snuff | Ever | Any | F | 35 | 107 | 2.67 (1.83–3.90)g | race, smok |
Wynder et al. 1983 [63] | Chew | Ever | Any | M | 36 | 37 | 1.00 (0.62–1.61)g | none |
 | Snuff |  |  |  | 37 | 12 | 0.42 (0.11–1.65)g |  |
 | ST |  |  |  | 38 | 49 | 0.90 (0.57–1.41)i |  |
Stockwell and Lyman 1986 [70] | ST | Ever | Any | M+F | 39 | 11 | 2.02 (1.01–4.02)g | none |
Young et al. 1986 [71] | ST | Ever | Any | M | 40 | NA | no association | none |
Blot et al. 1988 [74] | ST | Ever | Any | M | 41 | 46 | 0.85 (0.57–1.26)g | none |
 |  |  |  | F | 42 | 11 | 3.44 (1.09–10.91)g |  |
 |  |  | Never | F | 43 | 6 | 6.20 (1.90–19.80) | age, race, res, resp |
Spitz et al. 1988 [78] | Chew | Ever | Any | M+F | 44 | 23 | 1.00 (0.54–1.85)g | none |
 | Snuff |  |  |  | 45 | 9 | 3.40 (1.00–10.90) |  |
 | ST |  |  |  | 46 | 25 | 1.05 (0.57–1.91)g |  |
Franco et al. 1989 [80] | ST | Use | Any | M+F | 47 | 9 | 1.40 (0.59–3.33)g | none |
Blomqvist et al. 1991 [83] | Snuff | Ever | Never | M+F | 48 | 2 | 0.67 (0.08–5.75)g | none |
Maden et al. 1992 [85] | ST | Ever | Any | M | 49 | 19 | 4.50 (1.50–14.30) | age |
Marshall et al. 1992 [86] | Chew | Use | Any | M | 50 | NA | no significant association | none |
Sterling et al. 1992 [89] | ST | Ever | Any | M+F | 51 | 28g | 1.04 (0.41–2.68)g | age, alc, occ, race, sex, smok |
 | Snuff | Ever | Any | M+F | 52 | NA | 2.42 (1.28–4.59) | age, race, sex |
Mashberg et al. 1993 [90] | Chew | Ever | Any | Mf | 53 | NA | 1.00 (0.70–1.40) | age, alc, race, smok |
 | Snuff |  |  |  | 54 | NA | 0.80 (0.40–1.90) |  |
 | ST |  |  |  | 55 | 52 | 0.96 (0.70–1.33)i |  |
Perry et al. 1993j | ST | Use | Any | M+F | 56 | 10 | 1.43 (0.64–3.21)g | age, alc, occ, race, sex, smok |
Spitz et al. 1993 [92] | Chew | Use | Any | M+F | 57 | NA | 1.20 (not significant) | none |
Kabat et al. 1994 [97] | Chew | Ever | Any | M | 58 | 67 | 1.11 (0.81–1.53)g | smok |
 | Snuff | Ever | Never | M+F | 59 | 4 | 4.79 (1.19–19.30)g | none |
Bundgaard et al. 1995 [98] | Chew | Ever | Any | M+F | 60 | 8 | 1.44 (0.59–3.51)g | none |
Lewin et al. 1998 [102] | Snuff | Current | Any | M | 61 | 18 | 0.84 (0.47–1.50)g | age, alc, res, smok |
 |  | Former |  |  | 62 | 22 | 1.28 (0.70–2.35)g |  |
 |  | Ever |  |  | 63 | 40 | 0.98 (0.63–1.50)g |  |
Muscat et al. 1998 [103] | Chew | Ever | Any | M+F | 64 | 3 | 0.89 (0.18–4.49)g | none |
 | ST |  |  |  | 65 | 4 | 1.19 (0.26–5.45)i |  |
Schildt et al. 1998 [104] | Chew | Use | Any | M+F | 66 | 5 | 0.60 (0.20–2.00) | age, sex, res |
 | Snuff | Current |  |  | 67 | 39 | 0.70 (0.40–1.10) |  |
 |  | Former |  |  | 68 | 28 | 1.50 (0.80–2.90) |  |
 |  | Ever |  |  | 69 | 67 | 0.80 (0.50–1.30) | age, alc, sex, smok, res |
 |  | Current | Never |  | 70 | 19 | 0.70 (0.40–1.20) | age, sex, res |
 |  | Former |  |  | 71 | 9 | 1.80 (0.90–3.50) |  |
 |  | Ever |  |  | 72 | 28 | 1.01 (0.64–1.57)g |  |
 | ST | Ever | Any |  | 73 | 72 | 0.87 (0.61–1.25)i | none |
Schwartz et al. 1998 [105] | ST | Ever | Any | M | 74 | NA | 1.00 (0.40–2.30) | age, alc, smok |
Rosenquist et al. 2005 [113] | Snuff | Current | Any | M+F | 75 | 13 | 1.10 (0.50–2.50) | alc, smok |
 |  | Former |  |  | 76 | 7 | 0.30 (0.10–0.90) |  |
 |  | Ever |  |  | 77 | 20 | 0.70 (0.30–1.30) |  |