Abbott Diagnostics^ RF assay is used for the quantitative analysis of IgG RF in human serum using latex agglutination. Abbott says the test correlates well to nephelometric and turbidi- metric methods. The test can be performed on Abbotts Aeroset and Architect c8000 and ci8200 instruments. ... It can be used either manually or in conjunction with the companya#39;s MAGO Plus Automated ELISA processor.