. . "Longitudinal studies"@en . _:genid2 _:genid1 . _:genid1 . _:genid1 "Longitudinal studies" . _:genid2 . _:genid2 . . . . . . . . . "Use as a form subdivision under classes of persons, ethnic groups, and topical headings for works that report the results of longitudinal studies on those groups or topics." . "Reference under the heading {Longitudinal method}" . . . _:genid3 . _:genid3 "1999-03-01T00:00:00"^^ . _:genid3 "new"^^ . _:genid3 . _:genid3 . _:genid3 . _:genid4 . _:genid4 "2006-05-08T10:29:16"^^ . _:genid4 "revised"^^ . _:genid4 . _:genid4 . _:genid4 .