1. National Institute of Arthritis and Musculoskeletal and Skin DiseasesNIH Bethesda Maryland
2. Hospital de Santa Maria and Centro Hospitalar Universitário Lisboa Norte Lisbon Portugal
3. University of Oxford Oxford UK
4. University of the West of England Bristol UK
5. Auckland District Health Board Auckland New Zealand
6. University of East Anglia Norwich Medical School, Norwich, UK, and University of Oxford Oxford UK
7. University of Pennsylvania Philadelphia