1. Department of Statistics, Quaid-i-Azam University, Islamabad, Pakistan
2. Faculty of Health Studies, University of Bradford, Bradford BD7 1DP, UK
3. Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
4. Department of Statistics, COMSATS Institute of Information Technology, Lahore, Pakistan
5. Arriyadh Community College, King Saud University, Riyadh, Saudi Arabia
6. Workers University, Cairo, Egypt
7. College of Business Administration, King Saud University, Muzahimiyah, Saudi Arabia