1. Department of Psychiatry, United Arab Emirates University, Al-Ain, United Arab Emirates
2. Geriatrics and Gerontology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
3. Neurology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
4. Psychiatry Department, Ain Shams University, Cairo, Egypt
5. Old Age Psychiatry Service, Black Country Partnership NHS Foundation NHS Trust, West Bromwich, United Kingdom
6. Psychiatry Department, University of Warwick, Coventry, United Kingdom