Table 1 Study overview (included studies).
From: Meta-analysis of the relation between European and American smokeless tobacco and oral cancer
Study | First author, year of publication | Region | Study perioda | Designb | Sex | Case definition (or at risk populationc)d | Controls (or years of follow-upc) | Matching factorse |
|---|---|---|---|---|---|---|---|---|
1 | Broders 1920 [74] | USA | up to 1920 | CCH | M+F | NS | No lip cancer | NS |
2 | Moore 1953 [57] | USA | 1951–1952 | CCH | M | 50+ years | No cancer | NS |
3 | Wynder 1957 [58] | USA | up to 1957 | CCH | Mf | NS | Benign diseases, lymphoma, skin and gastrointestinal cancer | Age, rel, ins, ses |
4 | Peacock 1960 [93] | USA | 1952–1958 | CCH | M+F | With data on tobacco habits | No oral cancer | Sex, race, ins |
5 | Vogler 1962 [62] | USA | 1956–1957 | CCH | M+F | Incident and prevalent | No oral cancer | None |
6 | Vincent 1963 [94] | USA | up to 1963 | CCH | Mg | Incident | Successive gastrointestinal patients | Age |
7 | Martinez 1969 [95] | Puerto Rico | 1966 | CCH/P | M+F | Incident in 1966 | Patients without cancer and community controls | Age, sex |
8 | Keller 1970 [75] | USA | 1958–1962 | CCH | M | Discharged with complete records | No oral cancer | Age, hosp, time |
9 | Browne 1977 [96] | UK | 1957–1971 | CCP | M+F | NS | Community controls | Age, sex, occ, area |
10 | Williams 1977 [97] | USA | 1969–1971 | CCH | M+F | Incident, Third National Cancer Survey | No tobacco- or alcohol-related cancers | None |
11 | Wynder 1977 [98] | USA | 1969–1975 | CCH | M | Histologically confirmed | No tobacco-related diseases | Age, race, area |
12 | Westbrook 1980 [63] | USA | 1955–1975 | CCH | F | Incident | Unstated hospital controls | Age, time |
13 | Winn 1981 [13] | USA | 1975–1978 | CCH | F | Incident and death certificate | No oral cancer or mental disease | Age, race, type, area |
14 | Wynder 1983 [99] | USA | 1977–1980 | CCH | Mf | Histologically confirmed | No tobacco-related diseases | Age, race, hosp, ins |
15 | Stockwell 1986 [65] | USA | 1982 | CCP | M+F | Cancer registry 1982 | Melanoma or endocrine cancer | None |
16 | Blot 1988 [100] | USA | 1984–1985 | CCP | M+F | Incident | Population controls | Age, sex, area, race |
17 | Spitz 1988 [101] | USA | 1985–1987 | CCH | M+F | Registered 1985–1986, completed questionnaire, histologically confirmed with squamous cell carcinoma of defined sites | No squamous cell carcinoma | Age, sex |
18 | Franco 1989 [102] | Brazil | 1986–1988 | CCH | M+F | Incident, not lip or salivary glands | No cancer or mental disorder | Age, sex, area, time |
19 | Blomqvist 1991 [103] | Sweden | up to 1991 | CCH | M+F | NS | No cancer | Age, sex |
20 | Maden 1992 [104] | USA | 1985–1989 | CCP | M | Squamous cell, 18–65 years, with residential telephone | Population controls | Age, time |
21 | Sterling 1992 [67] | USA | 1986 | CCP | M+F | Registered in National Mortality Followback Study 1986, age 25+ years | Population controls | None |
22 | Zahm 1992 [72] | USA | 1954–1980 | Cohort | M | US veterans who returned questionnaire on tobacco use in 1954 or 1957 | Mortality 1954–1980 | NA |
23 | Mashberg 1993 [68] | USA | 1972–1983 | CCH | M | Incident in 1972–1983, US veterans | No cancer or dysplasia of pharynx, larynx, lung or oesophagus | None |
24 | Perry 1993h | USA | about 1992 | CCH | M+F | NS | Cardiovascular diseases | NS |
25 | Kabat 1994 [59] | USA | 1977–1990 | CCH | M+F | Incident | No tobacco-related diseases | Age, sex, race, hosp, time |
26 | Bundgaard 1995 [105] | Denmark | 1986–1990 | CCP | M+F | Histologically confirmed | Population controls | Age, sex, area |
27 | Lewin 1998 [64] | Sweden | 1988–1990 | CCP | M | Incident and registered, not identified at autopsy | Population controls | Age, area |
28 | Muscat 1998 [106] | USA | 1977–1990 | CCH | M+F | Incident, not mentally impaired | No tobacco-related diseases | Age, sex, race, time |
29 | Schildt 1998 [73] | Sweden | 1980–1989 | CCP | M+F | Histologically confirmed, not deceased without a relative | Population controls | Age, sex, area, vit |
30 | Schwartz 1998 [69] | USA | 1990–1995 | CCP | M+F | Histologically confirmed squamous cell carcinoma, 18–65 years | Population controls | Age, sex |
31 | Boffetta 2005 [82] | Norway | 1966–2001 | Cohort | M | Population sample and relatives of migrants to USA | Incidence 1966–2001 | NA |
32 | Henley 2005 [66] | USA | 1959–2000 | Cohort | M | Never smokers in Cancer Prevention Study I (CPS I) and II (CPS II) | Mortality CPS I : 1959 to 1972 CPS II : 1982 to 2000 | NA |