| Abnet 2001 |
age, gender, smoking, and alcohol |
| Abnet 2005 |
age and education |
| Dye 2007 |
age, gender, village, education, smoking |
| Guha 2007 |
age, gender, country/center, education, smoking, alcohol, and all other oral health variables |
| Abnet 2008 |
age, gender, place of residence, ethnicity, alcohol, smoking, opium, or both, education, number of appliances, and fruit and vegetable intake |
| Hiraki 2008 |
age, gender, tobacco, alcohol, vegetable and fruit intake, body mass index, and regular exercise |
| Michaud 2008 |
age, race, physical activity, history of diabetes, alcohol, body-mass index, geographical location, height, calcium intake, total calorific intake, red-meat intake, fruit and vegetable intake, vitamin D score, and smoking |
| Dar 2013 |
age, ethnicity, residence, education, wealth score, fruit and vegetable intake, bidi smoking, gutka chewing, alcohol consumption and cumulative use of hookah, cigarette, and nass |
