Table 1.
Potential explanatory variables in a United States multi-center, population-based case-control study of esophageal and gastric cancer (1993–1995)
| Demographic Variables | |
| Gender | Education (categorical, 7 levels) |
| Age (continuous) | Income (categorical, 6 levels) |
| Race (White/non-White) | |
| Dietary Variables† | |
| Fruit and other Juices | High-fat Dairy products |
| Citrus Fruit | Whole Grains |
| Non-citrus Fruit | Refined Grains |
| Cruciferous Vegetables | Fish |
| Deep yellow Vegetables | Poultry |
| Low Vitamin A cruciferous Vegetables | High-nitrite Meats |
| Dark green leafy Vegetables | Red Meats |
| Starchy Vegetables | Meat Alternates |
| Raw Vegetables | Nitrites (mg/day) |
| Dry beans and peas (legumes) | Dietary Fiber (mg/day) |
| Tomato products | Vitamin C (mg/day) |
| Low-fat Dairy products | Energy intake (Kcal/day) |
| Medical variables | |
| Body mass index (kg/m2) (continuous) | Gastroesophageal reflux symptoms (per year) |
| Lifestyle variables | |
| Beer (drinks/day) | Liquor (drinks/day) |
| Wine (drinks/day) | Cigarette smoking (cigarettes/day) |
†
Servings/day unless otherwise noted