Table 1 Characteristics of studies included in the meta-analysis

Stensvold & Jacobsen, 1994, Norway

M

10.1

35–54

21,735

46

FFQ

Norwegian Cancer Registry, death certificates

≥7cups/d vs. ≤ 2cups/d

0.68 (0.28–1.69)

No covariate adjustment

7

Stensvold & Jacobsen, 1994, Norway

F

10.1

35–54

21,238

32

FFQ

Norwegian Cancer Registry, death certificates

≥7cups/d vs. ≤ 2cups/d

0.47 (0.16–1.39)

No covariate adjustment

7

Bidel et al., 2013, Finland

M

18

26–74

29,159

181

Self-administered questionnaire

Finnish Cancer Registry

≥10cups/d vs. ≤ 0cup/d

0.53 (0.26–1.09)

Age, study year, education, cigarette smoking, alcohol consumption, leisure time physical activity, history of diabetes, tea consumption, and BMI

9

Bidel et al., 2013, Finland

F

18

26–74

30,882

118

Self-administered questionnaire

Finnish Cancer Registry

≥10cups/d vs. ≤ 0cup/d

2.07 (0.53–8.15)

Age, study year, education, cigarette smoking, alcohol consumption, leisure time physical activity, history of diabetes, tea consumption, and BMI

9

Larsson et al., 2006, Sweden

F

15.7

39–73

61,433

160

FFQ

National and Regional Swedish Cancer registry, (ICD-9 codes)

≥4cups/d vs. ≤ 1cup/d

1.86 (1.07–3.25)

Age, time period, education, alcohol intake and tea consumption

7

Jacobsen et al.,1986, Norway

M/F

11.5

35+

16,555

147

Self-administered questionnaire

Cancer Registry of Norway and deaths records from the Central Bureau of Statistics Registry, ICD-7 codes

≥7cups/d vs. ≤ 2cups/d

1.32 (0.76–2.30)

Sex, age and residence

7

Nilsson et al., 2010, Sweden

M/F

6

40–60

64,603

70

FFQ

Regional cancer registry, ICD-7codes

≥4cups/d vs. < 1cup/d

0.99 (0.44–2.21)

Age, sex, BMI, smoking, education, and recreational physical activity

7

Khan et al., 2004, Japan

M

13.8

40–97

1,524

36

Self-administered questionnaire

Medical records, ICD-9 codes

Took several times per week + took every day vs. took never + took several times per year + took several times per month

1.00 (0.50–2.00)

Age, smoking

9

Khan et al., 2004, Japan

F

14.8

40–97

1,634

15

Self-administered questionnaire

Medical records, ICD-9 codes

Took several times per week + took every day vs. took never + took several times per year + took several times per month

0.30 (0.10–1.40)

Age, health status, health education, health screening & smoking

9

Tsubono et al., 2001, Japan

M/F

9

40+

26,311

419

FFQ

Miyagi Prefectural Cancer Registry records

≥3cups/d vs. never

1.00 (0.60–1.60)

Sex; age; type of health insurance; history of peptic ulcer; cigarette smoking; alcohol consumption; daily consumption of rice; tea and consumption of meat, green or yellow vegetables, pickled vegetables, other vegetables, fruits, and bean-paste soup

9

Galanis et al., 1998, United States

M

14.8

18+

5,610

64

Self-administered questionnaire

Hawaii Tumor Registry

≥2cups/d vs. none

2.20 (0.90–5.30)

Age, years of education, Japanese place of birth, smoking and alcohol intake

8

Galanis et al., 1998, United States

F

14.8

18+

6,297

44

Self-administered questionnaire

Hawaii Tumor Registry

≥2cups/d vs. none

1.60 (0.70–3.80)

Age, years of education, Japanese place of birth, and smoking

8

Nomura et al., 1986, United States

M

15

45–68

7,355

106

Interview

Hawaii Tumor Registry

≥5cups/d vs. none

1.18 (0.61–2.27)

Age

8

van Loon et al., 1998, Netherlands

M

4.3

55–69

58,279

146

Self- administered questionnaire

Regional cancer registries in the Netherlands and with a national pathology register

>4cups/d vs. ≤ 3cups/d

1.5 (0.95–2.36)

No covariate adjustment

6

Ren et al., 2010, United States

M/F

5.4

50–71

481,563

231

FFQ

State cancer registry databases, ICD-3 codes

Cardia ≥3cups/d vs. < 1cup/d

1.57 (1.03–2.39)

Age, sex, tobacco smoking, alcohol drinking, BMI, education, ethnicity, usual physical activity throughout the day, vigorous physical activity, and the daily intake of fruit, vegetables, red meat, white meat, and calorie

7

Ren et al., 2010, United States

M/F

5.4

50–71

481,563

223

FFQ

State cancer registry databases, ICD-3 codes

Non-cardia ≥3cups/d vs. < 1cup/d

1.06 (0.68–1.64)

Age, sex, tobacco smoking, alcohol drinking, BMI, education, ethnicity, usual physical activity throughout the day, vigorous physical activity, and the daily intake of fruit, vegetables, red meat, white meat, and calorie

7

Ainslie-Waldman et al., 2014, Singapore

M

14.7

45–74

27,293

394

FFQ

Singapore Cancer Registry and the Singapore Registry of Births and Deaths

≥4cups/d vs. never/monthly

1.06(0.48–2.32)

Age, interview year, dialect, education, cigarette smoking status, number of cigarettes smoked per day, years smoked, BMI, caffeine, and total energy intake

9

Ainslie-Waldman et al., 2014, Singapore

F

14.7

45–74

34,028

253

FFQ

Singapore Cancer Registry and the Singapore Registry of Births and Deaths

≥4cups/d vs. never/monthly

0.76(0.23–2.53)

Age, interview year, dialect, education, cigarette smoking status, number of cigarettes smoked per day, years smoked, BMI, caffeine, and total energy intake

9

Sanikini et al., 2015, International

M

11.6

25–70

308,021

395

FFQ, recall record

Regional and national mortality registries, ICD-10 codes

≥557 ml/d vs. never/< 131 ml/d

1.51(1.06–2.16)

Age, center, smoking, BMI, physical activity, education level, diabetes, alcohol consumption, intake of energy, fiber, vegetable, fruit, fish and red and processed meat

9

Sanikini et al., 2015, International

F

11.6

25–70

169,291

288

FFQ, recall record

Regional and national mortality registries, ICD-10 codes

≥557 ml/d vs. never/< 131 ml/d

0.72(0.47–1.08)

Age, center, smoking, BMI, physical activity, education level, diabetes, alcohol consumption, intake of energy, fiber, vegetable, fruit, fish and red and processed meat

9