Table 2.

Case-control studies of smokeless tobacco and pancreatic cancer

Study Details	Third National Cancer Survey Study	Louisiana Study	Washington State Study	Quebec Study
Source	Williams et al [16]	Falk et al [20]	Farrow et al[12]	Ghadirian et al [21]
Country	USAa	USA	USA	Canada
Timing	1969–1971	1979–1983	1982–1986	1984–1988
Sex	Malesb	Males and females	Malesc	Males and females
Cases	Incident, pancreatic cancer	Incident, pancreatic cancer	Incident, pancreatic cancer	Diagnosed, pancreatic, bile duct or gall bladder cancer
Controls	Incident, cancers not associated with smoking	Hospital, without diet-altering chronic disease	Population, random-digit dialling	Population, random-digit dialling
Matching	None	Age, sex, race	Age, area	Age, sex, area
Surrogate respondents	None	> 50% (cases), 13% (controls)	100% (cases), 100% (controls)	75% (cases), 17% (controls)
Casesd	113e	363	168	179
Controlsd	2074e	1234	195	239
Data on ST usef	Chewing or snuff	Chewing, snuff	Chewing	Chewing
Adjustment factorsg	Age, race, smoking	Unstated	Race, education	Age, sex, smoking, education, proxy response
	Nine Hospital Study	Fifteen County Study	Texas Study
Source	Muscat et al [13]	Alguacil and Silverman [14]	Hassan et al [15]
Country	USAh	USAi	USA
Timing	1985–1993	1986–1989	2000–2006
Sex	Malesb	Males and females	Males and females
Cases	Incident, pancreatic cancer	Incident, exocrine pancreatic cancer	Incident, pancreatic adenocarcinoma
Controls	Hospital, diseases not associated with smoking	Population, random-digit diallingj	Hospital visitors, healthy, no cancer history
Matching	Age, sex, race, hospital, year of diagnosis	Age, sex, race	Age, sex, race
Surrogate respondents	None	None	None
Casesd	290e	154	808
Controlsd	572e	844	808
Data on ST usef	Chewing, snuff	Chewing or snuff	Chewing, snuff
Adjustment factorsg	None	Age, sex, race, site, cigar smoking	Age, sex, race, smoking, diabetes, alcohol, education, area, marital status

^a Nationwide

^b Females were also studied, but results were only available for males

^c Only married men were included

^d Numbers used in specific analyses may be less than this

^e Numbers are of males

^f "Chewing or snuff" implies that results were only available for combined ST use; "chewing, snuff" implies they were separately available

^g Adjustment factors used in analysis

^h Conducted in four hospitals in New York, two in Philadelphia, and one each in Chicago, and Detroit

ⁱ Conducted in two counties in Atlanta, three in Detroit and ten in the state of New Jersey

^j Controls aged 65–79 were drawn from Medicare and Medicaid service rosters