Table 1. The baseline characteristics of all study groups in this meta-analysis.
| Author (year) | Ethnicity | Cancer type | Match | Source of controls | Study design |
Sample size |
Age (years) |
Males |
BMI (kg/m2) |
Smoking |
Drinking |
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cases | Cont’s | Cases | Cont’s | Cases | Cont’s | Cases | Cont’s | Cases | Cont’s | Cases | Cont’s | ||||||
| Slattery (2014) | Mixed | Breast | NA | Population | Prosp. | 3567 | 4157 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Mandal (2014) | Caucasian | Prostate | YES | Hospital | Retrosp. | 84 | 78 | 59.8 | 57.2 | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Mandal (2014) | African-American | Prostate | YES | Hospital | Retrosp. | 80 | 62 | 67.9 | 64.0 | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Cil (2014) | Mixed | Thyroid | YES | Hospital | Retrosp. | 190 | 216 | 47.2 | 46.0 | 0.23 | 0.26 | 25.55 | 25.70 | 0.34 | 0.32 | NA | NA |
| Tindall (2012) | Caucasian | Prostate | YES | Population | Prosp. | 818 | 734 | NA | NA | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Giannitrapani (2011) | Caucasian | Liver | YES | Population | Retrosp. | 95 | 98 | NA | NA | 0.53 | NA | NA | NA | NA | NA | NA | NA |
| Giannitrapani (2011) | Caucasian | Liver | YES | Population | Retrosp. | 105 | 98 | NA | NA | 0.63 | NA | NA | NA | NA | NA | NA | NA |
| Gaur (2011) | Mixed | Oral | YES | Hospital | Prosp. | 140 | 120 | 51.4 | 51.4 | 0.85 | 0.85 | NA | NA | NA | NA | NA | NA |
| Abuli (2011) | Caucasian | Colorectal | YES | Population | Prosp. | 1405 | 1388 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Cacev (2010) | Caucasian | Colorectal | NA | Population | Retrosp. | 160 | 160 | 64.5 | 63.1 | 0.53 | 0.54 | NA | NA | NA | NA | NA | NA |
| Ognjanovic (2010) | Mixed | Colorectal | YES | Population | Retrosp. | 271 | 539 | 62.5 | 62.0 | 0.68 | 0.69 | 26.90 | 26.70 | 0.14 | 0.10 | 0.45 | 0.41 |
| Hawken (2010) | Mixed | Colorectal | NA | Population | Retrosp. | 1133 | 1125 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Dossus (2010) | Mixed | Breast | YES | Population | Prosp. | 6292 | 8135 | 63.1 | 63.1 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Dossus (2010) | Mixed | Prostate | YES | Population | Prosp. | 8008 | 8604 | 68.4 | 68.4 | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Tsilidis (2009) | Mixed | Colorectal | YES | Population | Prosp. | 208 | 318 | 62.8 | 62.8 | 0.46 | 0.45 | 26.30 | 26.00 | 0.13 | 0.13 | NA | NA |
| Ozgen (2009) | Mixed | Thyroid | NA | Hospital | Retrosp. | 42 | 340 | 43.1 | 43.8 | 0.19 | 0.19 | NA | NA | NA | NA | NA | NA |
| Ognjanovic (2009) | Mixed | Liver | YES | Population | Retrosp. | 120 | 230 | 60.5 | 59.5 | 0.68 | 0.60 | NA | NA | 0.42 | 0.28 | 0.71 | 0.77 |
| Gangwar (2009) | Asian | Cervical | YES | Hospital | Retrosp. | 160 | 200 | 45.0 | 46.0 | 0.00 | 0.00 | NA | NA | 0.34 | 0.10 | 0.06 | 0.01 |
| Falleti (2009) | Caucasian | Liver | NO | Population | Retrosp. | 219 | 236 | 53.0 | 46.0 | 0.70 | 0.70 | NA | NA | NA | NA | NA | NA |
| Cherel (2009) | Caucasian | Breast | NA | Hospital | Prosp. | 293 | 112 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Vasku (2009) | Caucasian | Colorectal | YES | Hospital | Retrosp. | 102 | 101 | 68.0 | 68.1 | 0.77 | 0.58 | NA | NA | NA | NA | NA | NA |
| Talar-Wojnarowska (2009) | Caucasian | Pancreatic | YES | Hospital | Retrosp. | 97 | 50 | NA | NA | 0.57 | 0.57 | NA | NA | NA | NA | NA | NA |
| Slattery (2009) | Mixed | Colorectal | NA | Population | Retrosp. | 1839 | 2014 | 0.55 | 0.54 | NA | NA | NA | NA | NA | NA | ||
| Andrie (2009) | Caucasian | Lymphoma | YES | Hospital | Retrosp. | 81 | 81 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Aladzsity (2009) | Caucasian | Myeloma | YES | Hospital | Retrosp. | 97 | 99 | 65.0 | 68.0 | 0.35 | 0.45 | NA | NA | NA | NA | NA | NA |
| Birmann (2009) | Mixed | Myeloma | NA | Population | Prosp. | 82 | 159 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Wilkening (2008) | Caucasian | Colorectal | YES | Population | Prosp. | 308 | 585 | 56.8 | 56.8 | 0.44 | 0.44 | NA | NA | NA | NA | NA | NA |
| Vairaktaris (2008) | Caucasian | Oral | YES | Population | Retrosp. | 162 | 168 | 58.5 | 54.7 | 0.80 | 0.75 | NA | NA | NA | NA | NA | NA |
| Upadhyay (2008) | Asian | Esophageal | YES | Hospital | Retrosp. | 168 | 201 | 56.8 | 53.7 | 0.74 | 0.75 | NA | NA | 0.82 | NA | 0.37 | NA |
| Slattery (2008) b | Caucasian | Breast | YES | Population | Retrosp. | 1176 | 1330 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Slattery (2008) a | Mixed | Breast | YES | Population | Retrosp. | 576 | 727 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Kesarwani (2008) | Asian | Prostate | YES | Population | Retrosp. | 200 | 200 | 62.5 | 59.5 | 1.00 | 1.00 | NA | NA | 0.32 | 0.30 | 0.60 | 0.69 |
| Crusius (2008) | Caucasian | Gastric | YES | Population | Prosp. | 439 | 1138 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Colakogullari (2008) | Mixed | Lung | YES | Population | Prosp. | 44 | 58 | 60.0 | NA | 0.91 | 0.51 | NA | NA | NA | NA | NA | NA |
| Bao (2008) | Asian | Prostate | YES | Hospital | Retrosp. | 136 | 120 | 62.8 | 62.3 | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Vogel (2008) | Caucasian | Lung | YES | Population | Retrosp. | 403 | 744 | NA | NA | 0.54 | 0.56 | NA | NA | 0.73 | 0.35 | NA | NA |
| Kury (2008) | Caucasian | Colorectal | YES | Hospital | Retrosp. | 1023 | 1121 | 65.7 | 61.9 | 0.62 | 0.54 | NA | NA | NA | NA | NA | NA |
| Ennas (2008) | Caucasian | Leukaemia | NO | Population | Retrosp. | 40 | 113 | 61.8 | 56.5 | 0.73 | 0.40 | NA | NA | NA | NA | NA | NA |
| Ahirwar (2008) | Asian | Bladder | YES | Population | Prosp. | 136 | 200 | 61.6 | 58.3 | 0.88 | 0.88 | NA | NA | NA | NA | NA | NA |
| Vishnoi (2007) | Asian | Gallbladder | YES | Population | Retrosp. | 45 | 82 | 49.4 | 50.0 | 1.00 | 1.00 | NA | NA | NA | NA | NA | NA |
| Vishnoi (2007) | Asian | Gallbladder | YES | Population | Retrosp. | 79 | 118 | 49.4 | 50.0 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Litovkin (2007) | Caucasian | Breast | YES | Population | Prosp. | 73 | 143 | 55.0 | 33.0 | 0.00 | 0.49 | NA | NA | NA | NA | NA | NA |
| Litovkin (2007) | Caucasian | Leiomyoma | YES | Population | Prosp. | 60 | 143 | 37.0 | 33.0 | 0.00 | 0.49 | NA | NA | NA | NA | NA | NA |
| Gonullu (2007) | Mixed | Breast | YES | Population | Retrosp. | 38 | 24 | 47.0 | 39.0 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Vogel (2007) | Caucasian | Breast | YES | Population | Prosp. | 361 | 361 | NA | NA | 0.00 | 0.00 | 25.00 | 25.00 | 0.34 | 0.36 | NA | NA |
| Vogel (2007) | Caucasian | Colorectal | YES | Population | Prosp. | 355 | 753 | 59.0 | 56.0 | 0.56 | 0.56 | 26.00 | 26.00 | 0.37 | 0.35 | NA | NA |
| Slattery (2007) | Mixed | Colorectal | YES | Population | Retrosp. | 1583 | 1979 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Slattery (2007) | Mixed | Colorectal | YES | Population | Retrosp. | 797 | 1011 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Nearman (2007) | Mixed | Leukaemia | NA | Hospital | Retrosp. | 28 | 362 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Gatti (2007) | Mixed | Gastric | NA | Hospital | Retrosp. | 56 | 56 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Duch (2007) | Mixed | Myeloma | YES | Hospital | Retrosp. | 52 | 60 | 58.5 | 59.3 | 0.42 | 0.60 | NA | NA | NA | NA | NA | NA |
| Deans (2007) | Caucasian | Gastric | NA | Population | Retrosp. | 203 | 224 | 71.0 | 39.2 | 0.66 | 0.53 | NA | NA | NA | NA | NA | NA |
| Berkovic (2007) | Caucasian | Gastric | YES | Hospital | Retrosp. | 80 | 162 | 80.0 | 46.5 | 0.48 | 0.48 | NA | NA | NA | NA | NA | NA |
| Vairaktaris (2006) | Caucasian | Oral | YES | Population | Retrosp. | 162 | 156 | 58.5 | 55.5 | 0.80 | 0.77 | NA | NA | NA | NA | NA | NA |
| Theodoropoulos (2006) | Caucasian | Colorectal | YES | Population | Prosp. | 222 | 200 | 64.7 | 62.7 | 0.58 | 0.60 | NA | NA | NA | NA | NA | NA |
| Nogueira (2006) | Mixed | Cervical | YES | Population | Retrosp. | 56 | 253 | 52.2 | 54.0 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Michaud (2006) | Mixed | Prostate | YES | Population | Prosp. | 503 | 652 | 67.1 | 66.6 | 1.00 | 1.00 | NA | NA | 0.08 | 0.11 | NA | NA |
| Kamangar (2006) | Caucasian | Gastric | YES | Population | Prosp. | 110 | 203 | 58.5 | 59.0 | 1.00 | 1.00 | NA | NA | 1.00 | 1.00 | NA | NA |
| Gonzalez-Zuloeta (2006) | Caucasian | Breast | NA | Population | Prosp. | 171 | 3651 | 67.8 | 70.8 | 0.00 | 0.00 | 26.70 | 27.10 | NA | NA | NA | NA |
| Balasubramanian (2006) | Caucasian | Breast | NA | Hospital | Prosp. | 197 | 490 | 63.0 | 57.0 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Rothman (2006) | Caucasian | Lymphoma | NA | Population | Retrosp. | 2658 | 3068 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Lan (2006) | Mixed | Lymphoma | YES | Population | Retrosp. | 518 | 597 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Gunter (2006) | Mixed | Colorectal | YES | Hospital | Retrosp. | 244 | 231 | 60.0 | 57.0 | 0.78 | 0.64 | 26.50 | 25.80 | 0.11 | 0.05 | NA | NA |
| Gaustadnes (2006) | Caucasian | Colorectal | YES | Population | Retrosp. | 230 | 540 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Cozen (2006) | Mixed | Myeloma | YES | Population | Retrosp. | 150 | 112 | 61.0 | NA | 0.61 | 0.58 | NA | NA | NA | NA | NA | NA |
| Seifart (2005) | Caucasian | Lung | NA | Population | Retrosp. | 182 | 243 | 63.3 | 37.9 | 0.88 | 0.55 | NA | NA | 0.98 | 0.40 | NA | NA |
| Migita (2005) | Asian | Liver | NO | Hospital | Prosp. | 48 | 188 | 62.5 | 51.5 | 0.81 | 0.68 | NA | NA | NA | NA | NA | NA |
| Leibovici (2005) | Caucasian | Bladder | YES | Hospital | Prosp. | 465 | 450 | NA | NA | NA | NA | NA | NA | 0.74 | 0.53 | NA | NA |
| Hefler (2005) | Caucasian | Breast | YES | Hospital | Retrosp. | 269 | 227 | 54.9 | 53.3 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Basturk (2005) | Mixed | Renal cell | YES | Population | Retrosp. | 29 | 50 | NA | NA | 0.05 | 0.56 | NA | NA | NA | NA | NA | NA |
| Snoussi (2005) | Caucasian | Breast | NA | Population | Prosp. | 305 | 200 | 50.0 | 46.0 | 0.01 | 0.05 | NA | NA | NA | NA | NA | NA |
| Skerrett (2005) | Mixed | Breast | NA | Population | Retrosp. | 88 | 102 | 49.2 | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Mazur (2005) | Caucasian | Myeloma | NA | Hospital | Retrosp. | 54 | 50 | 62.0 | NA | 0.43 | 0.58 | NA | NA | NA | NA | NA | NA |
| Festa (2005) | Caucasian | Basal cell | NA | Population | Prosp. | 241 | 260 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Cordano (2005) | Caucasian | Lymphoma | YES | Population | Retrosp. | 408 | 349 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Campa (2005) | Caucasian | Lung | NA | Hospital | Retrosp. | 1995 | 1982 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Zhang (2004) | Caucasian | Basal cell | YES | Hospital | Retrosp. | 241 | 260 | 50.0 | 48.0 | 0.58 | 0.54 | NA | NA | NA | NA | NA | NA |
| Smith (2004) | Caucasian | Breast | NO | Population | Retrosp. | 144 | 263 | 59.6 | 40.3 | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Campa (2004) | Caucasian | Lung | YES | Population | Prosp. | 250 | 214 | 63.1 | 64.8 | 0.71 | 0.75 | NA | NA | 0.73 | 0.91 | NA | NA |
| Bushley (2004) | Mixed | Ovarian | YES | Population | Retrosp. | 182 | 219 | NA | NA | 0.00 | 0.00 | NA | NA | NA | NA | NA | NA |
| Landi (2003) | Mixed | Colorectal | YES | Hospital | Retrosp. | 377 | 326 | NA | NA | 0.60 | 0.53 | NA | NA | 0.15 | 0.18 | 0.67 | 0.56 |
| El-Omar (2003) | Mixed | Esophageal | YES | Population | Retrosp. | 161 | 210 | 65.5 | 66.0 | 0.87 | 0.85 | NA | NA | 0.40 | 0.24 | 0.87 | 0.85 |
| El-Omar (2003) | Mixed | Gastric | YES | Population | Retrosp. | 314 | 210 | 68.0 | 66.0 | 0.81 | 0.85 | NA | NA | 0.30 | 0.24 | 0.75 | 0.85 |
| Hwang (2003) | Asian | Gastric | NA | Hospital | Retrosp. | 30 | 30 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Hwang (2003) | Caucasian | Gastric | NA | Hospital | Retrosp. | 30 | 30 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Howell (2003) | Caucasian | Melanoma | NA | Hospital | Prosp. | 153 | 208 | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Zheng (2000) | Caucasian | Myeloma | NA | Population | Retrosp. | 73 | 129 | 67.0 | NA | 0.45 | NA | NA | NA | NA | NA | NA | NA |
Abbreviations: BMI, body mass index; cont’s, controls; NA, not available; Prosp., prospective design; Retrosp., retrospective design.