Table 13

Larynx and nasal cancer; individual effect (relative risk/odds ratio) estimates

ST use

RR/OR

Source^a

Type^b

Exposure^c

Smoking

Sex

Id.

Cases^d

Estimate (95%CI)

Adjustment factors^e

Case-control studies

Wynder et al. 1957 [40]

- larynx cancer

Chew

Ever

Any

M

1

NA

no association^f

none

Vincent and Marchetta 1963 [45]

- larynx cancer

Snuff

Use

Any

M

2

5

1.81 (0.33–9.97)

none

Williams and Horm 1977 [55]

- larynx cancer

ST

Ever

Any

M

3

16

2.01 (1.15–3.51)^g

age, race, smok

Wynder and Stellman 1977 [56]

- larynx cancer

Chew

Ever

Any

M

4

46

1.35 (0.96–1.89)^g

none

Snuff

5

15

1.46 (0.82–2.57)^g

none

ST

6

61

1.40 (1.04–1.89)^h

none

Engzell et al. 1978 [57]

- nasal cancer

Snuff

Use

Any

M

7

NA

no association

none

Brinton et al. 1984 [64]

- nasal cancer

Chew

Use

Any

M+F

8

15

0.74 (0.40–1.50)

sex

Snuff

9

23

1.47 (0.80–2.80)

ST

10

38

1.08 (0.68–1.70)^h

none

Stockwell and Lyman 1986 [70]

- nasal cancer

ST

Ever

Any

M+F

11

1

2.93 (0.40–21.66)^g

none

- larynx cancer

ST

Ever

Any

M+F

12

6

2.02 (0.84–4.86)^g

none

Young et al. 1986 [71]

- larynx cancer

ST

Ever

Any

M

13

NA

no association

none

Lewin et al. 1998 [102]

- larynx cancer

Snuff

Current

Any

M

14

15

1.00 (0.50–1.90)

age, alc, res, smok

Former

15

9

0.80 (0.40–1.70)

Ever

16

24

0.90 (0.50–1.50)

^a Fuller details of the studies are given in Tables 1 and 2.

^b ST implies smokeless tobacco unspecified, or combined snuff use or chewing.

^c Ever, former and current ST use were compared with never ST. Use indicates timing not given and comparison is with non use.

^d 'Id.' is the RR/OR identification number used in Table 14, and 'Cases' is the number of cases in ST users as defined. NA = not available.

^e Abbreviations used: alc = alcohol, res = area of residence, smok = smoking.

^f The average ridit duration of chewing was non-significantly lower in the larynx cancer cases.

^g RR/OR and/or 95% CI estimated from data provided in the source.

^h RR/OR and/or 95% CI estimated from data provided in the source assuming that no one both chewed and used snuff.

CI = confidence interval; ST = smokeless tobacco; OR = odds ratio; RR = relative risk.

Lee and Hamling BMC Medicine 2009 7:36   doi:10.1186/1741-7015-7-36