Consider every bit of info you find anywhere is the result of a statement by another human. A few folks will watch a burial of someone and know the data is accurate at that time. Go back to the cemetery a couple years later as see what was placed on the grave marker. Throw in here inability to read, write, spell, local spellings, understandings of the spoken word, etc. and it is a wonder that we even get close on a lot of records. Census records are no different. SSDI is derived from what the funeral director told SS his data likely came from the death certificate which may or not be totally accurate. Bottom line, with all the diligence in the world, you are not going to be 100% accurate on anything. Cheers, Ron Submarine Vet.