1Division of Food Science and Culinary Arts, Food and Nutrition Major, Shinhan University, Uijeongbu, Korea
2Department of Cancer Control and Policy, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
3Molecular Epidemiology Branch, Division of Cancer Epidemiology and Prevention, Research Institute, National Cancer Center, Goyang, Korea
4Department of Family Medicine, Center for Cancer Prevention and Detection, Hospital, National Cancer Center, Goyang, Korea
5School of Nursing, Shinhan University, Uijeongbu, Korea
Copyright © 2017 by the Korean Cancer Association
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Study | Type of study | Country | Years enrolled | Population (sex, age) | Type of thyroid cancer | Definition of alcohol use (highest vs. lowest category) | OR/RR (95% Cl) | Adjusted variable |
---|---|---|---|---|---|---|---|---|
Takezaki et al. (1996) [16] | Case-control study | Japan | 1988-1993 | 94 cases and 26,666 controls (women, 20-79 yr) | Papillary or follicular thyroid cancer | Sometimes or less/≥ 4 times/wk | 0.70 (0.30-1.50) | Age and year of visit |
Rossing et al. (2000) [17] | Case-control study | United States | 1988-1994 | 468 cases and 574 controls, (women, 18-64 yr) | Papillary thyroid cancer | 7 drinks/wk, vs. never, 1 drink: not specified | 0.90 (0.50-1.40) | Age, country of residence, race, marital status, education, history of radiation treatment, and smoking |
fribarren et al. (2001) [18] | Prospective cohort study | United States | 1964-1973 | 204,964 persons and 169 cases (men and women, 10-89 yr) | All types of thyroid cancer | ≥ 6 drinks/day vs. 1-2 drinks/day, 1 drink: not specified | 0.95 (0.30-3.02) | Age, sex, race, level of education, cigarette smoking, self-reported personal history, family history of thyroid disease, body mass index, weight gain, height, and occupational exposures |
Mack et al. (2003) [11] | Pooled analysis of 14 case-control studies | United States, Europe, and Asia | 1980-1997 | 2,725 cases and 4,776 controls (men and women, all ages) | All types of thyroid cancer | > 14 drinks/wk vs. none, 1 drink: one glass of wine or beer | 0.90 (0.70-1.10) | Study, sex, and age |
Navarro Silvera et al. (2005) [19] | Prospective cohort study | Canada | 1980-1985 | 89,835 persons and 169 cases (women, 40-59 yr) | All types of thyroid cancer | ≥ 10 g/day vs. none | 0.84 (0.44-1.58) | Age, education, BMI, and pack-years of smoking |
Nagano et al. (2007) [21] | Case-control study | Japan | 1970-1986 | 362 cases and 435 controls (men and women, > 75 yr) | Papillary or follicular thyroid cancer | Daily vs. never | 0.59 (0.35-1.01) | Family history of cancer, past history of goiter or thyroid nodule, and smoking history |
Guignard et al. (2007) [20] | Case-control study | New Caledonia | 1993-1999 | 332 cases and 412 controls (men and women ≥ 70 yr) | Papillary or follicular thyroid cancer | > 10 drinks/wk vs. never, 1 drink: an ordinary glass of any alcoholic beverage | 0.64 (0.22-1.88) | Age, year of reference, ethnic group, and number of pack-years |
Allen et al. (2009) [22] | Prospective cohort study | United Kingdom | 1996-2001 | 1,280,296 persons and 421 cases (women, average 55 yr) | All types of thyroid cancer | ≥ 15 drinks/wk vs. none, 1 drink: about 10 g of alcohol | 0.54 (0.31-0.92) | Age, region of residence, socioeconomic status,BMI, smoking, physical activity, use of oral contraceptives, and hormone replacement therapy |
Meinhold et al. (2009) [23] | Prospective cohort study | United States | 1995-1996 | 490,159 persons and 370 cases (men and women, 50-71 yr) | All types of thyroid cancer | ≥ 2 drinks/day vs. none, 1 drink: 12.96 g-13.93 g of ethanol according to type of alcoholic beverage | 0.57 (0.36-0.89) | Age, sex, race, education, smoking status, BMI, and family history of cancer |
Meinhold et al. (2010) [24] | Prospective cohort study | United States | 1983-2006 | 90,713 persons and 282 cases (men and women, all years) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: not specified | 0.86 (0.54-1.39) | Birth year, smoking, BMI, number of radiographs to the head and neck, and medical history of benign thyroid conditions |
Han et al. (2011) [25] | Cross-sectional study | Korea | 2009 | 2,000 persons and 263 cases (≥ 40 yr men, ≥ 30 yr women) | All types of thyroid cancer | ≥ 1 frequency/mo vs. none | 0.61 (0.44-0.86) | Age, residence, education, income, marital status, job, self-rated health, smoking, and vigorous exercise |
Kabat et al. (2012) [26] | Prospective cohort study | United States | 1993-1998 | 159,340 persons and 331 cases (women, 50-79 yr) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: not specified | 0.66 (0.44-1.01) | Age, education, pack-years of smoking, age of first pregnancy, age at menopause, hormone therapy, history of benign thyroid disease, observational study component/clinical trial component, and randomization status in CT |
Kitahara et al. (2012) [12] | Pooled analysis of five prospective cohort studies | United States | 1983-2009 | 746,097 persons and 1,003 cases (men and women, all years) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: 14 g of alcohol | 0.72 (0.58-0.90) | Age, sex, education, race, marital status, BMI, and smoking status |
Choi et al. (2013) [27] | Cross-sectional study | Korea | 2010-2011 | 12,276 persons and 71 cases (men and women, all years) | All types of thyroid cancer | Drinking vs. non-drinking | 1.89 (1.08-3.32) | Age, sex, weight, height, survey year, monthly household income, education, marital status, residential area, smoking, and physically active |
Xhaard et al. (2014) [28] | Case-control study | French Polynesia | 1981-2003 | 229 cases and 373 controls men and women, 10-62 yr) | All types of thyroid cancer | Regular alcohol consumption yes vs. no | 1.20 (0.30-4.50) | BMI, height, number of pregnancies, menopausal status, nuclear worker, family history of thyroid cancer, education, and irradiation of the neck |
Stansifer et al. (2015) [29] | Retrospective case-control study | United States | 2013 | 467 cases and 255 controls (men and women, ≥ 18 yr) | All types of thyroid cancer | Current drinker vs. never drinker | 0.46 (0.29-0.73) | None |
Case-control studies (n=6) |
Cohort studies (n=6) |
|||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Takezaki et al. (1996) [16] | Rossing et al. (2000) [17] | Nagano et al. (2007) [21] | Guignard et al. (2007) [20] | Xhaard et al. (2014) [28] | Stansifer et al. (2015) [29] | Iribarren et al. (2001) [18] | Navarro Silvera et al. (2005) [19] | Allen et al. (2009) [22] | Meinhold et al. (2009) [23] | Meinhold et al. (2010) [24] | Rabat et al. (2012) [26] | |
Selection | ||||||||||||
Adequate definition of cases | 1 | 0 | 1 | 1 | 1 | 0 | - | - | - | - | - | - |
Representativeness of cases | 1 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Selection of controls | 0 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Definition of controls | 1 | 0 | 1 | 1 | 0 | 1 | - | - | - | - | - | - |
Comparability | - | - | - | - | - | - | ||||||
Control for important factor or additional factor | 2 | 2 | 2 | 2 | 2 | 0 | - | - | - | - | - | - |
Exposure | ||||||||||||
Ascertainment of exposure (blinding) | 0 | 0 | 1 | 0 | 0 | 0 | - | - | - | - | - | - |
Same method of ascertainment for participants | 1 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Nonresponse rate | 0 | 0 | 1 | 1 | 0 | 0 | - | - | - | - | - | - |
Total | 6 | 5 | 9 | 8 | 6 | 4 | - | - | - | - | - | - |
Selection | ||||||||||||
Representativeness of the exposed cohort | - | - | - | 1 | 1 | 1 | 1 | 0 | 1 | |||
Selection of the nonexposed cohort | - | - | - | - | - | - | 1 | 1 | 1 | 1 | 1 | 1 |
Ascertainment of exposure | - | - | - | - | - | - | 0 | 0 | 0 | 0 | 0 | 0 |
Outcome of interest was not present at start of study | - | - | - | - | - | - | 0 | 1 | 1 | 1 | 1 | 0 |
Comparability | ||||||||||||
Control for important factor or additional factor | - | - | - | - | - | - | 2 | 2 | 2 | 2 | 2 | 2 |
Outcome | ||||||||||||
Assessment of outcome | - | - | - | - | - | - | 1 | 1 | 1 | 1 | 1 | 1 |
Follow-up long enough for outcomes to occur | - | - | - | - | - | - | 1 | 1 | 1 | 0 | 1 | 1 |
Adequacy of follow-up of cohorts | - | - | - | - | - | - | 0 | 0 | 0 | 0 | 0 | 1 |
Total | - | - | - | - | - | - | 6 | 7 | 7 | 6 | 6 | 7 |
a) Each study can be awarded a maximum of one star for each numbered item within the selection and exposure categories, while a maximum of two stars can be given for the comparability category,
b) Two pooled studies [11,12] with 14 case-control studies and five cohort studies and a cross-sectional study were excluded from this assessment of methodological quality because no required information for the methodological assessment of each study was provided.
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All [11,12,16-19] | 33 | 0.74 (0.67-0.83) | 38.6 | Fixed-effect |
Type of cancer | ||||
All types of thyroid cancer [11,12,18,19,22-29] | 29 | 0.74 (0.62-0.89) | 52.3 | Random-effects |
Papillary thyroid cancer [17,19,23,26] | 4 | 0.70 (0.55-0.91) | 0 | Fixed-effect |
Papillary or follicular thyroid cancer [16,19-21] | 4 | 0.68 (0.48-0.96) | 0 | Fixed-effect |
Sex | ||||
Female [16,17,19-26] | 10 | 0.71 (0.60-0.84) | 0 | Fixed-effect |
Male [20,21,23-25] | 5 | 0.57 (0.39-0.82) | 0 | Fixed-effect |
Region | ||||
America [12,17-19,23,24,26,29] | 12 | 0.70 (0.60-0.81) | 0 | Fixed-effect |
Europe [22,28] | 2 | 0.60 (0.36-1.00) | 13.1 | Fixed-effect |
Asia [16,21,25,27] | 4 | 0.82 (0.48-1.42) | 76.3 | Random-effects |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [11,12,17,20,22-24,26] | 25 | 0.89 (0.82-0.97) | 0 | Fixed-effect |
1-6 Drinks/wk [12,17,20,22-24,26] | 11 | 0.83 (0.76-0.92) | 15.5 | Fixed-effect |
7-14 Drinks/wk [11,12,17,20-24,26,29] | 27 | 0.75 (0.67-0.83) | 15.0 | Fixed-effect |
> 14 Drinks/wk [11,18,22,23] | 17 | 0.80 (0.67-0.96) | 30.2 | Fixed-effect |
Type of alcohol | ||||
Wine [11,23] | 15 | 0.95 (0.76-1.19) | 0 | Fixed-effect |
Beer [11,23] | 15 | 0.63 (0.34-1.16) | 66.3 | Random-effects |
Wine and beer [11] | 14 | 0.90 (0.70-1.10) | NA | Fixed-effect |
Liquor [23] | 1 | 1.02 (0.68-1.53) | NA | Fixed-effect |
Methodological quality | ||||
High quality [19-22,26] | 5 | 0.64 (0.50-0.82) | 0 | Fixed-effect |
Low quality [16-18,23,24,28,29] | 7 | 0.68 (0.55-0.85) | 6.7 | Fixed-effect |
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All Low quality [11,16,17,20,21,28,29] | 20 | 0.77 (0.65-0.92) | 29.5 | Fixed-effect |
Type of cancer | ||||
All types of thyroid cancer [11,28,29] | 16 | 0.72 (0.41-1.25) | 71.1 | Random-effects |
Papillary thyroid cancer [17] | 1 | 0.90 (0.50-1.40) | NA | Fixed-effect |
Papillary or follicular thyroid cancer [16,20,21] | 3 | 0.62 (0.41-0.94) | 0 | Fixed-effect |
Sex | ||||
Female [16,17,20,21] | 4 | 0.84 (0.59-1.19) | 0 | Fixed-effect |
Male [20,21] | 2 | 0.35 (0.12-1.03) | 0 | Fixed-effect |
Region | ||||
America [17,29] | 2 | 0.64 (0.33-1.23) | 72.4 | Fixed-effect |
Asia [16,21] | 2 | 0.62 (0.40-0.97) | 0 | Fixed-effect |
Europe [28] | 1 | 1.20 (0.30-4.50) | NA | Fixed-effect |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [11,17,20] | 16 | 0.80 (0.68-0.93) | 25.1 | Fixed-effect |
1-6 Drinks/wk [17,20] | 2 | 0.54 (0.39-0.75) | 0 | Fixed-effect |
7-14 Drinks/wk [11,17,20,21,29] | 18 | 0.72 (0.52-0.98) | 53.5 | Random-effects |
> 14 Drinks/wk [11] | 14 | 0.90 (0.70-1.10) | NA | Fixed-effect |
Methodological quality | ||||
High quality [20,21] | 2 | 0.60 (0.37-0.96) | 0 | Fixed-effect |
Low quality [16,17,28,29] | 4 | 0.65 (0.48-0.89) | 33.5 | Fixed-effect |
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All [12,18,19,22-24,26] | 11 | 0.70 (0.60-0.82) | 0 | |
Type of cancer | ||||
All types of thyroid cancer [12,18,19,22-24,26] | 11 | 0.70 (0.60-0.82) | 0 | Fixed-effect |
Papillary thyroid cancer [19,23,26] | 3 | 0.65 (0.49-0.87) | 0 | Fixed-effect |
Papillary or follicular thyroid cancer [19] | 1 | 0.84 (0.44-1.58) | NA | Fixed-effect |
Sex | ||||
Female [19,22-24,26] | 5 | 0.67 (0.53-0.84) | 0 | Fixed-effect |
Male [23,24] | 2 | 0.70 (0.43-1.14) | 0 | Fixed-effect |
Region | ||||
America [12,18,19,23,24,26] | 10 | 0.72 (0.61-0.84) | 0 | Fixed-effect |
Europe [22] | 1 | 0.54 (0.31-0.92) | NA | Fixed-effect |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [12,22-24,26] | 9 | 0.93 (0.85-1.03) | 0 | Fixed-effect |
1-6 Drinks/wk [12,22-24,26] | 9 | 0.87 (0.78-0.96) | 0 | Fixed-effect |
7-14 Drinks/wk [12,22-24,26] | 9 | 0.71 (0.62-0.82) | 0 | Fixed-effect |
> 14 Drinks/wk [18,22,23] | 3 | 0.66 (0.49-0.88) | 0 | Fixed-effect |
Methodological quality | ||||
High quality [19,22,26] | 3 | 0.66 (0.49-0.88) | 0 | Fixed-effect |
Low quality [18,23,24] | 3 | 0.71 (0.52-0.97) | 0 | Fixed-effect |
Study | Type of study | Country | Years enrolled | Population (sex, age) | Type of thyroid cancer | Definition of alcohol use (highest vs. lowest category) | OR/RR (95% Cl) | Adjusted variable |
---|---|---|---|---|---|---|---|---|
Takezaki et al. (1996) [16] | Case-control study | Japan | 1988-1993 | 94 cases and 26,666 controls (women, 20-79 yr) | Papillary or follicular thyroid cancer | Sometimes or less/≥ 4 times/wk | 0.70 (0.30-1.50) | Age and year of visit |
Rossing et al. (2000) [17] | Case-control study | United States | 1988-1994 | 468 cases and 574 controls, (women, 18-64 yr) | Papillary thyroid cancer | 7 drinks/wk, vs. never, 1 drink: not specified | 0.90 (0.50-1.40) | Age, country of residence, race, marital status, education, history of radiation treatment, and smoking |
fribarren et al. (2001) [18] | Prospective cohort study | United States | 1964-1973 | 204,964 persons and 169 cases (men and women, 10-89 yr) | All types of thyroid cancer | ≥ 6 drinks/day vs. 1-2 drinks/day, 1 drink: not specified | 0.95 (0.30-3.02) | Age, sex, race, level of education, cigarette smoking, self-reported personal history, family history of thyroid disease, body mass index, weight gain, height, and occupational exposures |
Mack et al. (2003) [11] | Pooled analysis of 14 case-control studies | United States, Europe, and Asia | 1980-1997 | 2,725 cases and 4,776 controls (men and women, all ages) | All types of thyroid cancer | > 14 drinks/wk vs. none, 1 drink: one glass of wine or beer | 0.90 (0.70-1.10) | Study, sex, and age |
Navarro Silvera et al. (2005) [19] | Prospective cohort study | Canada | 1980-1985 | 89,835 persons and 169 cases (women, 40-59 yr) | All types of thyroid cancer | ≥ 10 g/day vs. none | 0.84 (0.44-1.58) | Age, education, BMI, and pack-years of smoking |
Nagano et al. (2007) [21] | Case-control study | Japan | 1970-1986 | 362 cases and 435 controls (men and women, > 75 yr) | Papillary or follicular thyroid cancer | Daily vs. never | 0.59 (0.35-1.01) | Family history of cancer, past history of goiter or thyroid nodule, and smoking history |
Guignard et al. (2007) [20] | Case-control study | New Caledonia | 1993-1999 | 332 cases and 412 controls (men and women ≥ 70 yr) | Papillary or follicular thyroid cancer | > 10 drinks/wk vs. never, 1 drink: an ordinary glass of any alcoholic beverage | 0.64 (0.22-1.88) | Age, year of reference, ethnic group, and number of pack-years |
Allen et al. (2009) [22] | Prospective cohort study | United Kingdom | 1996-2001 | 1,280,296 persons and 421 cases (women, average 55 yr) | All types of thyroid cancer | ≥ 15 drinks/wk vs. none, 1 drink: about 10 g of alcohol | 0.54 (0.31-0.92) | Age, region of residence, socioeconomic status,BMI, smoking, physical activity, use of oral contraceptives, and hormone replacement therapy |
Meinhold et al. (2009) [23] | Prospective cohort study | United States | 1995-1996 | 490,159 persons and 370 cases (men and women, 50-71 yr) | All types of thyroid cancer | ≥ 2 drinks/day vs. none, 1 drink: 12.96 g-13.93 g of ethanol according to type of alcoholic beverage | 0.57 (0.36-0.89) | Age, sex, race, education, smoking status, BMI, and family history of cancer |
Meinhold et al. (2010) [24] | Prospective cohort study | United States | 1983-2006 | 90,713 persons and 282 cases (men and women, all years) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: not specified | 0.86 (0.54-1.39) | Birth year, smoking, BMI, number of radiographs to the head and neck, and medical history of benign thyroid conditions |
Han et al. (2011) [25] | Cross-sectional study | Korea | 2009 | 2,000 persons and 263 cases (≥ 40 yr men, ≥ 30 yr women) | All types of thyroid cancer | ≥ 1 frequency/mo vs. none | 0.61 (0.44-0.86) | Age, residence, education, income, marital status, job, self-rated health, smoking, and vigorous exercise |
Kabat et al. (2012) [26] | Prospective cohort study | United States | 1993-1998 | 159,340 persons and 331 cases (women, 50-79 yr) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: not specified | 0.66 (0.44-1.01) | Age, education, pack-years of smoking, age of first pregnancy, age at menopause, hormone therapy, history of benign thyroid disease, observational study component/clinical trial component, and randomization status in CT |
Kitahara et al. (2012) [12] | Pooled analysis of five prospective cohort studies | United States | 1983-2009 | 746,097 persons and 1,003 cases (men and women, all years) | All types of thyroid cancer | ≥ 7 drinks/wk vs. none, 1 drink: 14 g of alcohol | 0.72 (0.58-0.90) | Age, sex, education, race, marital status, BMI, and smoking status |
Choi et al. (2013) [27] | Cross-sectional study | Korea | 2010-2011 | 12,276 persons and 71 cases (men and women, all years) | All types of thyroid cancer | Drinking vs. non-drinking | 1.89 (1.08-3.32) | Age, sex, weight, height, survey year, monthly household income, education, marital status, residential area, smoking, and physically active |
Xhaard et al. (2014) [28] | Case-control study | French Polynesia | 1981-2003 | 229 cases and 373 controls men and women, 10-62 yr) | All types of thyroid cancer | Regular alcohol consumption yes vs. no | 1.20 (0.30-4.50) | BMI, height, number of pregnancies, menopausal status, nuclear worker, family history of thyroid cancer, education, and irradiation of the neck |
Stansifer et al. (2015) [29] | Retrospective case-control study | United States | 2013 | 467 cases and 255 controls (men and women, ≥ 18 yr) | All types of thyroid cancer | Current drinker vs. never drinker | 0.46 (0.29-0.73) | None |
Case-control studies (n=6) |
Cohort studies (n=6) |
|||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Takezaki et al. (1996) [16] | Rossing et al. (2000) [17] | Nagano et al. (2007) [21] | Guignard et al. (2007) [20] | Xhaard et al. (2014) [28] | Stansifer et al. (2015) [29] | Iribarren et al. (2001) [18] | Navarro Silvera et al. (2005) [19] | Allen et al. (2009) [22] | Meinhold et al. (2009) [23] | Meinhold et al. (2010) [24] | Rabat et al. (2012) [26] | |
Selection | ||||||||||||
Adequate definition of cases | 1 | 0 | 1 | 1 | 1 | 0 | - | - | - | - | - | - |
Representativeness of cases | 1 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Selection of controls | 0 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Definition of controls | 1 | 0 | 1 | 1 | 0 | 1 | - | - | - | - | - | - |
Comparability | - | - | - | - | - | - | ||||||
Control for important factor or additional factor | 2 | 2 | 2 | 2 | 2 | 0 | - | - | - | - | - | - |
Exposure | ||||||||||||
Ascertainment of exposure (blinding) | 0 | 0 | 1 | 0 | 0 | 0 | - | - | - | - | - | - |
Same method of ascertainment for participants | 1 | 1 | 1 | 1 | 1 | 1 | - | - | - | - | - | - |
Nonresponse rate | 0 | 0 | 1 | 1 | 0 | 0 | - | - | - | - | - | - |
Total | 6 | 5 | 9 | 8 | 6 | 4 | - | - | - | - | - | - |
Selection | ||||||||||||
Representativeness of the exposed cohort | - | - | - | 1 | 1 | 1 | 1 | 0 | 1 | |||
Selection of the nonexposed cohort | - | - | - | - | - | - | 1 | 1 | 1 | 1 | 1 | 1 |
Ascertainment of exposure | - | - | - | - | - | - | 0 | 0 | 0 | 0 | 0 | 0 |
Outcome of interest was not present at start of study | - | - | - | - | - | - | 0 | 1 | 1 | 1 | 1 | 0 |
Comparability | ||||||||||||
Control for important factor or additional factor | - | - | - | - | - | - | 2 | 2 | 2 | 2 | 2 | 2 |
Outcome | ||||||||||||
Assessment of outcome | - | - | - | - | - | - | 1 | 1 | 1 | 1 | 1 | 1 |
Follow-up long enough for outcomes to occur | - | - | - | - | - | - | 1 | 1 | 1 | 0 | 1 | 1 |
Adequacy of follow-up of cohorts | - | - | - | - | - | - | 0 | 0 | 0 | 0 | 0 | 1 |
Total | - | - | - | - | - | - | 6 | 7 | 7 | 6 | 6 | 7 |
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All [11,12,16-19] | 33 | 0.74 (0.67-0.83) | 38.6 | Fixed-effect |
Type of cancer | ||||
All types of thyroid cancer [11,12,18,19,22-29] | 29 | 0.74 (0.62-0.89) | 52.3 | Random-effects |
Papillary thyroid cancer [17,19,23,26] | 4 | 0.70 (0.55-0.91) | 0 | Fixed-effect |
Papillary or follicular thyroid cancer [16,19-21] | 4 | 0.68 (0.48-0.96) | 0 | Fixed-effect |
Sex | ||||
Female [16,17,19-26] | 10 | 0.71 (0.60-0.84) | 0 | Fixed-effect |
Male [20,21,23-25] | 5 | 0.57 (0.39-0.82) | 0 | Fixed-effect |
Region | ||||
America [12,17-19,23,24,26,29] | 12 | 0.70 (0.60-0.81) | 0 | Fixed-effect |
Europe [22,28] | 2 | 0.60 (0.36-1.00) | 13.1 | Fixed-effect |
Asia [16,21,25,27] | 4 | 0.82 (0.48-1.42) | 76.3 | Random-effects |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [11,12,17,20,22-24,26] | 25 | 0.89 (0.82-0.97) | 0 | Fixed-effect |
1-6 Drinks/wk [12,17,20,22-24,26] | 11 | 0.83 (0.76-0.92) | 15.5 | Fixed-effect |
7-14 Drinks/wk [11,12,17,20-24,26,29] | 27 | 0.75 (0.67-0.83) | 15.0 | Fixed-effect |
> 14 Drinks/wk [11,18,22,23] | 17 | 0.80 (0.67-0.96) | 30.2 | Fixed-effect |
Type of alcohol | ||||
Wine [11,23] | 15 | 0.95 (0.76-1.19) | 0 | Fixed-effect |
Beer [11,23] | 15 | 0.63 (0.34-1.16) | 66.3 | Random-effects |
Wine and beer [11] | 14 | 0.90 (0.70-1.10) | NA | Fixed-effect |
Liquor [23] | 1 | 1.02 (0.68-1.53) | NA | Fixed-effect |
Methodological quality | ||||
High quality [19-22,26] | 5 | 0.64 (0.50-0.82) | 0 | Fixed-effect |
Low quality [16-18,23,24,28,29] | 7 | 0.68 (0.55-0.85) | 6.7 | Fixed-effect |
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All Low quality [11,16,17,20,21,28,29] | 20 | 0.77 (0.65-0.92) | 29.5 | Fixed-effect |
Type of cancer | ||||
All types of thyroid cancer [11,28,29] | 16 | 0.72 (0.41-1.25) | 71.1 | Random-effects |
Papillary thyroid cancer [17] | 1 | 0.90 (0.50-1.40) | NA | Fixed-effect |
Papillary or follicular thyroid cancer [16,20,21] | 3 | 0.62 (0.41-0.94) | 0 | Fixed-effect |
Sex | ||||
Female [16,17,20,21] | 4 | 0.84 (0.59-1.19) | 0 | Fixed-effect |
Male [20,21] | 2 | 0.35 (0.12-1.03) | 0 | Fixed-effect |
Region | ||||
America [17,29] | 2 | 0.64 (0.33-1.23) | 72.4 | Fixed-effect |
Asia [16,21] | 2 | 0.62 (0.40-0.97) | 0 | Fixed-effect |
Europe [28] | 1 | 1.20 (0.30-4.50) | NA | Fixed-effect |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [11,17,20] | 16 | 0.80 (0.68-0.93) | 25.1 | Fixed-effect |
1-6 Drinks/wk [17,20] | 2 | 0.54 (0.39-0.75) | 0 | Fixed-effect |
7-14 Drinks/wk [11,17,20,21,29] | 18 | 0.72 (0.52-0.98) | 53.5 | Random-effects |
> 14 Drinks/wk [11] | 14 | 0.90 (0.70-1.10) | NA | Fixed-effect |
Methodological quality | ||||
High quality [20,21] | 2 | 0.60 (0.37-0.96) | 0 | Fixed-effect |
Low quality [16,17,28,29] | 4 | 0.65 (0.48-0.89) | 33.5 | Fixed-effect |
Factor | No. of studies | Summary OR or RR (95% CI) | Heterogeneity, I2 (%) | Model used |
---|---|---|---|---|
All [12,18,19,22-24,26] | 11 | 0.70 (0.60-0.82) | 0 | |
Type of cancer | ||||
All types of thyroid cancer [12,18,19,22-24,26] | 11 | 0.70 (0.60-0.82) | 0 | Fixed-effect |
Papillary thyroid cancer [19,23,26] | 3 | 0.65 (0.49-0.87) | 0 | Fixed-effect |
Papillary or follicular thyroid cancer [19] | 1 | 0.84 (0.44-1.58) | NA | Fixed-effect |
Sex | ||||
Female [19,22-24,26] | 5 | 0.67 (0.53-0.84) | 0 | Fixed-effect |
Male [23,24] | 2 | 0.70 (0.43-1.14) | 0 | Fixed-effect |
Region | ||||
America [12,18,19,23,24,26] | 10 | 0.72 (0.61-0.84) | 0 | Fixed-effect |
Europe [22] | 1 | 0.54 (0.31-0.92) | NA | Fixed-effect |
Amount of alcohol consumed (vs. never or rarely drink) | ||||
≤ 1-2 Drinks/wk [12,22-24,26] | 9 | 0.93 (0.85-1.03) | 0 | Fixed-effect |
1-6 Drinks/wk [12,22-24,26] | 9 | 0.87 (0.78-0.96) | 0 | Fixed-effect |
7-14 Drinks/wk [12,22-24,26] | 9 | 0.71 (0.62-0.82) | 0 | Fixed-effect |
> 14 Drinks/wk [18,22,23] | 3 | 0.66 (0.49-0.88) | 0 | Fixed-effect |
Methodological quality | ||||
High quality [19,22,26] | 3 | 0.66 (0.49-0.88) | 0 | Fixed-effect |
Low quality [18,23,24] | 3 | 0.71 (0.52-0.97) | 0 | Fixed-effect |
OR, odd ratio; RR, relative risk; CI, confidence interval; BMI, body mass index; CT, computed tomography.
Each study can be awarded a maximum of one star for each numbered item within the selection and exposure categories, while a maximum of two stars can be given for the comparability category, Two pooled studies [11,12] with 14 case-control studies and five cohort studies and a cross-sectional study were excluded from this assessment of methodological quality because no required information for the methodological assessment of each study was provided.
OR, odd ratio; RR, relative risk; CI, confidence interval; NA, not applicable.
OR, odd ratio; RR, relative risk; CI, confidence interval; NA, not applicable.
OR, odd ratio; RR, relative risk; CI, confidence interval; NA, not applicable.