Fig. 2.
A schematic representation of the multiparty computation scenario. Any time prior to the protocol execution each of the medical centers computes their local contingency tables, and secret shares them to the three computation servers, as indicated in step ① of the protocol. In step ②, the computation servers securely compute the χ2 value, and perform a secure comparison to determine whether the value is significant or not. This reveals no information about the inputs, or the actual χ2 value to the individual computation servers. In step ③ the computation servers reconstruct the final result, which indicates significance or non-significance, by combining their individual secret shares, and they publish this result in the public table