1. Department of Epidemiology and statistics, Healthy Ageing Research Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran
2. Department of Basic Medical Sciences, Healthy Ageing Research Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran
3. Department of Basic Medical Sciences, Non-Communicable Diseases Research Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran
4. Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Science, Tehran, Iran
5. Department of Cardiology, Research Center for Prevention of Cardiovascular Endocrinology & Metabolism, Research Institute Hazrat-e Rasool General Hospital, Iran University of Medical Sciences, Tehran, Iran
6. Department of Internal Medicine, Tuberculosis and Lung Diseases Research Centre, Tabriz University of Medical Sciences, Tabriz, Iran
7. Department of Internal Medicine, Connective Tissue Diseases Research Centre, Tabriz University of Medical Sciences, Tabriz, Iran
8. Department of Psychiatrics, Shiraz Geriatric Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran
9. Longitudinal Study on Ageing Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran
10. Department of Cardiology, Healthy Ageing Research Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran
11. Centre for Innovative Ageing, College of Human and Health Sciences, Swansea University, Swansea, UK
12. Department of Medical Gerontology, Trinity College Dublin, Ireland
13. Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON Canada
14. School of Psychology, Massey University, Palmerston North, New Zealand
15. Digestive Diseases Research Centre, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran