Quality assurance and proficiency testing for autoantibodies to nuclear antigen.

The College of American Pathologists' Proficiency Survey results have shown a need for standardization of testing for autoantibodies to nuclear antigens (ANA). We have recommended that each laboratory establish age-adjusted reference ranges for particular methods and instrumentation, report qualitative end point titers in relation to these reference ranges, interpret normal or abnormal as a laboratory appraisal rather than as a clinical assessment, and inclusion of a low-titer ANA control sera in each assay.