Quantitation of rheumatoid factor activity by nephelometry.

Rheumatoid factor activity can be quantitated by use of nephelometric assay system. The data presented show a good correlation between this new method and the older quantitative latex tube rheumatoid factor test. In addition, the nephelometric and latex tube testing of sera from normal, rheumatoid and non-rheumatoid patients yielded similar results, suggesting the two procedures share a similar immunologic specificity. The new nephelometric test for rheumatoid factor is simple to perform, endpoints are objectively determined, and test data are highly reproducible.