The limited effects of obstetrical and neonatal complications on conduct and attention-deficit hyperactivity disorder symptoms in middle childhood.

Objective: The purpose of this study was to examine the effects of a wide range of obstetrical and neonatal complications as well as socioeconomic variables on the behaviors characterized by attention-deficit hyperactivity disorder, conduct disorder, and oppositional defiant disorder.

Method: Data were collected on 7- to 8-year old twins, using multiple instruments assessing many areas of individual and family functioning. The influence of several aspects of prenatal care, labor and delivery, and early life were considered as well as indicators of socioeconomic status, such as family income and maternal education.