Studies of adoptees from psychiatrically disturbed biologic parents. II. Temperament, hyperactive, antisocial, and developmental variables.

Temperament, hyperactivity, antisocial behavior, and developmental milestones were assessed in two groups of adoptees by interviewing the adoptive parents. One group, the "experimental," was born of psychiatrically disturbed biologic parents (N = 59). The second group, the "control," had psychiatrically "normal" parents (N = 54). Infants in each group were separated from their biologic parents at birth and had no further contact with them. Male "experimental" adoptees had excess number of temperament traits characteristic of the "difficult" child, as well as an excess of antisocial behaviors when contrasted with male control subjects. No differences between control and experimental females were found for these variables. Hyperactive behavior in the adoptees of each sex was associated more with antisocial parentage than in those of "normal" parentage.