I am posting this for Jeff Smith, Assistant Registrar for Collections
Information at the Freer and Sackler Galleries, Smithsonian Institution:

I'm curious how other TMS users handle the expression of uncertain values
in
any number of fields.

The AAT guidelines for dates recommend a question mark instead of
"possibly" or "probably" - both of which affect sorting and searching. Yet
in geographic or historical context fields such as period, a "?" is
awkward.

Has anyone developed a comprehensive decision for this issue?

Thanks.