Table 1.
Characteristics of the studies included in the review.
| Study | Country | Design | Study population | Age | Diet quality index1 | Dietary method | Follow-up & outcome assessment | Adjustments |
|---|---|---|---|---|---|---|---|---|
| Arthur et al. (9) | US | Cohort study | 108,136 postmenopausal women | 50 to 79 years | Diet score of 6 dietary components (cereal fiber, red and processed meat, the ratio of polyunsaturated to saturated fat, trans-fats, glycemic load, and fruits and vegetables |
122-item self-administered food frequency questionnaire | Median follow-up of 17.9 years; 904 ovarian cancer cases and 1,435 endometrial cancer cases; Cancer diagnoses and tumor characteristics were adjudicated centrally by trained physicians, who reviewed medical records and pathology reports |
Age at entry, education, nonalcohol energy intake, ethnicity, age at menarche, parity, combined estrogen and progesterone therapy, unopposed estrogen therapy, oral contraceptive use, family history of endometrial or ovarian cancer, age at menopause, physical activity, alcohol consumption, body mass index, and smoking |
| Arthur et al. (12) | Canada | Case-cohort design | 2735 women | Median age for cohort was 58 years | Healthy Diet Score including information on intake of cereal fiber, red and processed meat, margarine, and fruits and vegetables. |
166-item self-administered food frequency questionnaire | Median follow-up of 11 years; 100 ovarian cancer cases and 177 endometrial cancer cases |
Stratified by age at entry and adjusted for education, non-alcohol energy intake, smoking status, alcohol intake, body mass index, diet score, physical activity, age at menarche, parity, menopause, hormone replacement therapy use, oral contraceptive use |
| Qin et al. (10) | US | Population-based case-control study | 415 ovarian cases and 629 controls; Cases were newly diagnosed and histologically confirmed invasive epithelial ovarian cancer from cancer registries or hospitals’ gynecologic oncology departments; Controls had no previous history of ovarian cancer, and had not had previous bilateral oophorectomy, identified by list-assisted, random-digit dialing |
20 to 79 years | Healthy Eating Index -2005, Healthy Eating Index -2010, and Alternative Healthy Eating Index -2010 | Self-administered Block 2005 food frequency questionnaire for 110 foods and beverages | NA | Age, region, education, parity, oral contraceptive use, menopause status, tubal ligation status, first-degree family history of breast/ovarian cancer, body mass index, physical activity, and total energy intake. |
| Ricceri et al. (13) | Italy | a case-control study | 297 women with newly diagnosed endometrial cancer and 307 controls |
40 to 74 years | Mediterranean Diet Score | Validated food frequency questionnaire | NA | Age, age at menarche, parity, oral contraceptive use, menopausal status, use of hormone replacement therapy, body mass index, physical activity, education, smoking status, and total energy intake. |
| Filomeno et al. (14) | Italy | Pooled analysis of three hospital based case-control studies |
1411 endometrial cancer cases and 3668 controls | Median age of cases was 61 year; median age of controls was 57 years | Mediterranean Diet Score | Validated food frequency questionnaire | NA | Age, study center, year of interview, education, tobacco smoking, body mass index, age at menopause, age at menarche, parity, oral contraceptive use, hormone-replacement therapy use, history of hypertension, diabetes and total energy intake. |
| George et al. (15) | US | Cohort study | 84,415 postmenopausal women | 50 to 79 years | Healthy Eating Index -2010, Alternative Healthy Eating Index -2010, alternate Mediterranean Diet Score, and Dietary Approaches to Stop Hypertension | Self-administered, validated food frequency questionnaire | 13.3 years of follow-up; 1,392 endometrial cancer cases |
Age, energy intake, ethnicity, education, leisure time physical activity, diabetes status, postmenopausal hormone replacement therapy use, oral contraceptive use, age at first birth, participant in Observational Study, participant in HT trial, participant in DM trial |
| Xie et al. (11) | US | Cohort study | 82,948 female registered nurses | 30 to 55 years | Healthy Eating Index -2005, Alternative Healthy Eating Index -2010, and alternate Mediterranean Diet Score | Self-administered semi-quantitative, 131-item, validated food frequency questionnaire | Over 24 years of follow-up; 696 ovarian cancer cases; Ovarian cancer cases were identified either by self-report of the disease on a biennial questionnaire or through family members, the postal service, or the National Death Index |
Age, total energy intake, family history of ovarian cancer, tubal ligation, body mass index, parity, number of additional pregnancies, oral contraceptive use duration, smoking (pack-years), menopausal status, type and duration of postmenopausal hormone use, age at menarche, hysterectomy, unilateral oophorectomy, lactose intake, caffeine intake, and physical activity |
| Chandran et al. (16) | US | Population-based case-control study |
205 ovarian cancer cases and 390 controls; Cases were newly diagnosed, pathologically confirmed of invasive epithelial ovarian cancer from the Cancer Registry; Controls were recruited by random digit dialing and confirmed not with a history of hysterectomy and/or bilateral oophorectomy |
Mean ages for cases and controls were 57 and 64.6 years | Healthy Eating Index -2005 | Block 98.2 food frequency questionnaire for 110 food items | NA | Age, education, race, age at menarche, menopausal status, parity, oral contraceptive use, hormone replacement therapy use, tubal ligation, body mass index, total energy intake, physical activity, smoking status, and pack years smoked |
| Chandran et al. (17) | US | Population-based case- control study |
424 endometrial cancer cases and 398 controls | The mean age was 61.6 years for cases and 64.3 years for controls | Healthy Eating Index -2005 | Block 98.2 food frequency questionnaire for 110 food items | NA | Age, education, race, age at menarche, menopausal status and age at menopause for postmenopausal women, parity, oral contraceptive use, hormone replacement therapy use, body mass index, and total calories, physical activity, smoking status, and alcohol |
| Mai et al. (18) | US | Cohort study | 42 254 women | mean age of 61 years | Recommended Foods Score (including information on fruits, vegetables, whole grains, lean meats or meat alternatives, low-fat dairy) | 62-item Block/NCI food frequency questionnaire | Median follow-up period of 9.5 years; 142 ovarian cancer cases and 263 endometrial cancer cases; Self-reports of any newly diagnosed cancers. Medical records were obtained to confirm information. Deaths were identified by linkage with the National Death Index and/or the mailed questionnaire. |
Age, energy intake, smoking, non-steroidal anti-inflammatory drug use, and body mass index |
| Harnack et al. (19) | US | Cohort study | 34708 postmenopausal women | 55 to 69 years | the fifth edition of the Dietary Guidelines for Americans (including fruits, vegetables, grains, milk, meat, saturated fat, cholesterol, total fat, sweetened beverages, sodium, alcohol weight, physical activity) | Self-administered, validated food frequency questionnaire for 127 food items | 13 year of follow-up; 164 ovarian cancer cases; Cancer diagnosis was ascertained through the State Health Registry of Iowa |
Age, energy intake, smoking status, pack-years of cigarette smoking, age at menopause, family history of ovarian cancer in first-degree relatives, nulliparity |
1Healthy Eating Index-2005 includes components of total fruit (included 100% juice), whole fruit (not juice), total vegetables, dark green and orange vegetables and legumes, total grains, whole grains, milk, meat and beans, oils, saturated fat, sodium, calories from solid fat, alcohol and added sugar; Healthy Eating Index-2010 includes components of total fruit (all forms of fruit, including fruit juice), whole fruit (all forms except fruit juice), total vegetables, greens and beans, whole grains, dairy, total protein foods (lean portion of meat and poultry; eggs; beans and peas), seafood and plant proteins, fatty acids (ratio of polyunsaturated and monounsaturated fatty acids to saturated fatty acids), refined grains, sodium, empty calories (calories from solid fats, alcohol and added sugars); Alternative Healthy Eating Index-2010 includes components of fruit, vegetables, whole grains, soda and fruit juice, nuts and legumes, processed/red meat, trans fat, long-chain (n-3) fats, polyunsaturated fatty acids, sodium and alcohol; Mediterranean Diet Score includes components of vegetables (excluding potatoes), fruit (including juices), legumes, nuts, fish, ratio of monounsaturated fat to saturated fat, red and processed meats and alcohol; Dietary Approaches to Stop Hypertension includes components of fruit (all fruits and fruit juice), vegetables (all vegetables except potatoes and legumes), nuts and legumes, whole grains, low-fat dairy, sodium, red and processed meats, sweetened beverages.