Antinuclear Antibodies Testing Method Variability: A Survey of Participants in the College of American Pathologists’ Proficiency Testing Program

S.J. Naides, MD, Scientific Affairs, Euroimmun US, a PerkinElmer company, Mountain Lakes, New Jersey, and Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; J.R. Genzen, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology, University of Utah / ARUP Laboratories, Salt Lake City, Utah; G. Abel, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Laboratory Medicine and Pathology, Lahey Hospital & Medical Center, Beth Israel Lahey Health, Burlington, Massachusetts; C. Bashleben, MT, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; M.Q. Ansari, MD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology and Laboratory Medicine, Louis Stokes VAMC, Cleveland, Ohio, USA. This work was supported by the College of American Pathologists Diagnostic Immunology and Flow Cytometry Committee. Dr. S.J. Naides is employed by Euroimmun US. Dr. J.R. Genzen is employed by University of Utah/ARUP Laboratories, and is the principal investigator and contract researcher at ARUP Laboratories, Fujirebio Diagnostics. Address correspondence to Dr. S.J. Naides, Euroimmun US, 1 Bloomfield Avenue, Mountain Lakes, NJ 07046, USA. Email: stanley.naides@euroimmun.us. Accepted for publication February 28, 2020.

S.J. Naides, MD, Scientific Affairs, Euroimmun US, a PerkinElmer company, Mountain Lakes, New Jersey, and Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; J.R. Genzen, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology, University of Utah / ARUP Laboratories, Salt Lake City, Utah; G. Abel, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Laboratory Medicine and Pathology, Lahey Hospital & Medical Center, Beth Israel Lahey Health, Burlington, Massachusetts; C. Bashleben, MT, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; M.Q. Ansari, MD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology and Laboratory Medicine, Louis Stokes VAMC, Cleveland, Ohio, USA. This work was supported by the College of American Pathologists Diagnostic Immunology and Flow Cytometry Committee. Dr. S.J. Naides is employed by Euroimmun US. Dr. J.R. Genzen is employed by University of Utah/ARUP Laboratories, and is the principal investigator and contract researcher at ARUP Laboratories, Fujirebio Diagnostics. Address correspondence to Dr. S.J. Naides, Euroimmun US, 1 Bloomfield Avenue, Mountain Lakes, NJ 07046, USA. Email: stanley.naides@euroimmun.us. Accepted for publication February 28, 2020.

S.J. Naides, MD, Scientific Affairs, Euroimmun US, a PerkinElmer company, Mountain Lakes, New Jersey, and Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; J.R. Genzen, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology, University of Utah / ARUP Laboratories, Salt Lake City, Utah; G. Abel, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Laboratory Medicine and Pathology, Lahey Hospital & Medical Center, Beth Israel Lahey Health, Burlington, Massachusetts; C. Bashleben, MT, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; M.Q. Ansari, MD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology and Laboratory Medicine, Louis Stokes VAMC, Cleveland, Ohio, USA. This work was supported by the College of American Pathologists Diagnostic Immunology and Flow Cytometry Committee. Dr. S.J. Naides is employed by Euroimmun US. Dr. J.R. Genzen is employed by University of Utah/ARUP Laboratories, and is the principal investigator and contract researcher at ARUP Laboratories, Fujirebio Diagnostics. Address correspondence to Dr. S.J. Naides, Euroimmun US, 1 Bloomfield Avenue, Mountain Lakes, NJ 07046, USA. Email: stanley.naides@euroimmun.us. Accepted for publication February 28, 2020.

S.J. Naides, MD, Scientific Affairs, Euroimmun US, a PerkinElmer company, Mountain Lakes, New Jersey, and Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; J.R. Genzen, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology, University of Utah / ARUP Laboratories, Salt Lake City, Utah; G. Abel, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Laboratory Medicine and Pathology, Lahey Hospital & Medical Center, Beth Israel Lahey Health, Burlington, Massachusetts; C. Bashleben, MT, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; M.Q. Ansari, MD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology and Laboratory Medicine, Louis Stokes VAMC, Cleveland, Ohio, USA. This work was supported by the College of American Pathologists Diagnostic Immunology and Flow Cytometry Committee. Dr. S.J. Naides is employed by Euroimmun US. Dr. J.R. Genzen is employed by University of Utah/ARUP Laboratories, and is the principal investigator and contract researcher at ARUP Laboratories, Fujirebio Diagnostics. Address correspondence to Dr. S.J. Naides, Euroimmun US, 1 Bloomfield Avenue, Mountain Lakes, NJ 07046, USA. Email: stanley.naides@euroimmun.us. Accepted for publication February 28, 2020.

S.J. Naides, MD, Scientific Affairs, Euroimmun US, a PerkinElmer company, Mountain Lakes, New Jersey, and Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; J.R. Genzen, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology, University of Utah / ARUP Laboratories, Salt Lake City, Utah; G. Abel, MD, PhD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Laboratory Medicine and Pathology, Lahey Hospital & Medical Center, Beth Israel Lahey Health, Burlington, Massachusetts; C. Bashleben, MT, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois; M.Q. Ansari, MD, Diagnostic Immunology and Flow Cytometry Committee, College of American Pathologists, Northfield, Illinois, and Pathology and Laboratory Medicine, Louis Stokes VAMC, Cleveland, Ohio, USA. This work was supported by the College of American Pathologists Diagnostic Immunology and Flow Cytometry Committee. Dr. S.J. Naides is employed by Euroimmun US. Dr. J.R. Genzen is employed by University of Utah/ARUP Laboratories, and is the principal investigator and contract researcher at ARUP Laboratories, Fujirebio Diagnostics. Address correspondence to Dr. S.J. Naides, Euroimmun US, 1 Bloomfield Avenue, Mountain Lakes, NJ 07046, USA. Email: stanley.naides@euroimmun.us. Accepted for publication February 28, 2020.