The differential impact of birth order and IQ on sibling roles were examined with particular interest focused on achievement outcomes. Subjects were a stratified sample of 37 pairs of near-in-age siblings, all within the normal range in personality and IQ, but differing significantly in scores on the Slosson IQ Test. Results indicate that when the…

A private corporation conducted a study for the United States Air Force in 1973, investigating the long term effects of drug use on general mental ability. The air force personnel selected for participation in the study were 3741 known drug users and 6772 controls. Subjects received requests to sign a form allowing their high schools to release…

Evaluated demographic and developmental differences in case studies of disturbed children (N=58) who were treated with developmental therapy. Results indicated children differed in age, intelligence, and mother's employment status. Although all children progressed in behavior, communication, socialization, and academics, no difference was found in…

A study designed to examine biological, sociological, and early maturational correlates of intelligence collected data prospectively, from birth to 15 years of age, on a sample of 987 black children. Multiple indicators of eight independent and three dependent variables were tested in a structural equation model. Altogether, clear sex differences…