Gido-sanshi, which Korechika used to refer to himself, was used in the Sui and Tang dynasties in China as Kaifu Yitong Sansi (Supreme Minister), indicating a sankan, a position which was given, with no specific role provided, to civil officers at the rank of ju-ippin.
伊周の称した儀同三司とは、中国の隋唐両代において、開府儀同三司と呼ばれ従一品の文官が帯びる散官で、特に職掌はなかった。