378 Subfield $q - Fuller form of personal name:

Subfield $q contains a full form of name needed to distinguish a person from another person with the same preferred name.

Examples:

100  1#  $aJohnson, A.W.$q(Alva William)

378  ##  $qAlva William

100  0#  $aH. D.$q(Hilda Doolittle)

378  ##  $qHilda Doolittle