Correlate as named by investigatorPeople investigatedFinding
Age of first head lifting
31-33 aged, born at the university hospital, Denmark, 1993
Age of first smile
31-33 aged, born at the university hospital, Denmark, 1993
Age of first holding head up
31-33 aged, born at the university hospital, Denmark, 1993
Age of first sitting without support
31-33 aged, born at the university hospital, Denmark, 1993
Age of first crawling without support
31-33 aged, born at the university hospital, Denmark, 1993
Age of first walking with support
31-33 aged, born at the university hospital, Denmark, 1993
Age of first standing without support
31-33 aged, born at the university hospital, Denmark, 1993
Age of first walking without support
31-33 aged, born at the university hospital, Denmark, 1993
Age of first tooth
31-33 aged, born at the university hospital, Denmark, 1993
Ability to sit after 1 year
31-33 aged, born at the university hospital, Denmark, 1993
Early versus late maturation
Highschool pupils, Oakland, USA, 1932, followed from age 12 to 38, 1959