1. Centre for Disaster Medicine, University of Gothenburg , Box 426, Göteborg 413 45, Sweden
2. Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg , Göteborgsvägen 31, Mölndal 431 80, Sweden
3. Centre for Defence Medicine, Swedish Armed Forces , Göta Älvsgatan 20, Västra Frölunda 426 05, Sweden
4. Department of Orthopaedics, Sahlgrenska University Hospital , Länsmansgatan 28, Mölndal 431 30, Sweden
5. Occupational Performance Research Group, Institute of Applied Sciences, University of Chichester , College Lane, Chichester, West Sussex PO19 6PE, Great Britain