1. Division of Rheumatology University of Washington Seattle Washington USA
2. Holden Comprehensive Cancer Center (HCCC) University of Iowa Iowa City Iowa USA
3. Division of Allergy and Immunology University of Iowa Iowa City Iowa USA
4. Mayo Clinic Division of Biomedical Statistics and Informatics Rochester Minnesota USA
5. Mayo Clinic Division of Epidemiology Rochester Minnesota USA
6. Division of Hematology and Oncology University of Iowa Iowa City Iowa USA