1. Department of Statistics, Quaid-i-Azam University, Islamabad, Pakistan;
2. Johann Bernoulli Institute Groningen University, Groningen, Netherlands;
3. Faculty of Health Studies, University of Bradford, Bradford, UK;
4. Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK;
5. Department of Mathematics, King Khalid University, Abha, Saudi Arabia;
6. Department of Mathematics and Statistics, International Islamic University Islamabad, Pakistan;
7. Department of Statistics, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan;
8. Department of Statistics, University of Sargodha, Sargodha, Pakistan