1. Department of Family Medicine and Population Health, Division of Epidemiology and Community Health, Virginia Commonwealth University, Richmond, VA, USA
2. Department of Physical Medicine and Rehabilitation, Oslo University Hospital, Oslo, Norway
3. Institute of Health and Society, Research Centre for Habilitation and Rehabilitation Models and Services (CHARM), Faculty of Medicine, University of Oslo, Oslo, Norway
4. Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA, USA