The ELISA has been assessed in larger numbers of individuals in such studies than the ELISpot. In a recent systematic review the specificity of the ELISA ranged from 89 to 100% with a pooled specificity of 99% for the second-generation ELISA and 96% for the latest generation, in-tube ELISA. The pooled specificity of the ELISpot was also high: 93% (range 85–100%).It is better explained thus
Note that the two meta studies did not use the FDA approved criteria for T-Spot TB which fails counts of 5,6 or 7 spots.
