Table 1

 Diagnostic value of RF, anti-CCP and anti-RA33 autoantibodies. Data in the overall patient population

(n = 102)(n = 98)(%)(%)(%)
PPV, positive predictive value.
High titre RF (⩾50 U/ml) and anti-CCP both showed high specificity and comparable sensitivity, whereas low titre RF occurred with similar frequency in the RA and in the non-RA group.
RF (>20 U/ml) (n)5611558984
High titre RF (⩾50 U/ml) (n)464459692
Anti-CCP (n)422419896
Anti-RA33 (n)2910289074