1. Departments of Rheumatology and Research & Development, Dudley Group NHS Foundation Trust (Teaching Trust of University of Birmingham, UK), Russells Hall Hospital, Dudley, West Midlands, UK.
2. Department of Statistics and Econometrics, Stavropol State Agrarian University, Stavropol, Russian Federation.
3. Department of Marketing and Trade Deals, Kuban State University, Krasnodar, Russian Federation.
4. Arthritis Research UK Epidemiology Unit, University of Manchester, Manchester, United Kingdom.