Indexes of agreement between each pair of laboratories in North America for the designation of positive vs. negative for each subject based on the first visit for which each pair of labs both provided a result

AutoantibodiesCellular immunoblotTCPTetramerU.S.-ELISPOT
Autoantibodies0.51 (64)0.10 (81)0.11 (59)0.11 (45)
Cellular immunoblot0.200.25 (67)0.14 (53)−0.012 (46)
TCP0.0080.050.09 (63)0.03 (55)
Tetramer0.0090.0150.007−0.29 (47)
  • Data are κ (n of concurrent evaluations) and entropy R2. κ < 0 designates worse-than-chance agreement.