Trance Mediumship vs Non-Trance Mediums

It is important that the medium bring through verifiable evidence that they would have no normal way of knowing. I don't know of any other grounds for believing other information that can't be verified - whether they are in a trance or not, or whether they are psychologists using hypnosis doing past life or inter-life regression.

UPDATE: Cross correspondences might be an exception - if you get parts of a message through multiple independent mediums who don't know others are also involved and the message doesn't make sense unless the parts are combined - that is evidence there is an intelligence behind it even if you can't verify the message independently.