The Taipei Adolescent Twin/sibling Family Study I: behavioral problems, personality features, and neuropsychological performance.

The present study aimed to investigate genetic and environmental influences on behavioral problems, personality features, and neuropsychological performance among adolescents in Taipei, Taiwan. Between 1996 and 1998, with the assistance of the Twin Association and junior high schools in Taipei City, we solicited a list of twins from 51 junior high schools in Taipei. Names, addresses, and telephone numbers of the twins enrolled in these schools were obtained. The vast majority of the recruited twins were between 12 and 16 years old. The recruited twins received assessments for behavioral problems, general and schizotypal personality, and cognitive functions. Their parents rated their children on behavioral/ emotional problems and were assessed on their own general and specific personality. Same-sex sibling pairs (ages vary within 2 years) and their parents from three schools were also recruited to increase sample size for the group with a kinship coefficient of .50. Twins' zygosity was determined by a combination of DNA typing and physical similarity. The Mx program was used to estimate parameters for the full model and its reduced models. The recruitment, measurements, data managements, and published results are described in this article.