Irwin D. Waldman1, Soo Hyun Rhee1, Sarah A. Feigon1, & Jessica L. Bar1
In this paper we describe a new registry of 1600 twin pairs, ages 6 - 18, that were recruited over the past 4 years. Through a search of computerized birth records, we identified all multiple births in the state of Georgia during 1973-1991 and were given access to their complete birth records. Using parents' social security numbers, we then located the twin families' current addresses and conducted our first mailing consisting of an invitation to join the registry and a family information form. This form comprised demographic questions regarding family composition, family income, and the age, ethnicity, education, and occupation of family members, as well as a number of questions regarding physical similarity that were used to determine twins' zygosity. The registry is socioeconomically and ethnically diverse, with a substantial representation of African-American families. Twins and their families from this registry are participating in a series of research projects on personality and psychopathology in children. We are currently conducting a mailed questionnaire study of personality and temperament and have completed a mailed questionnaire study of DSM-IV externalizing and internalizing symptoms. My graduate students and I are using these twin data to investigate a number of issues in the classification of child psychopathology and its relation to personality. Specific issues include: testing alternative models for sex differences in Attention Deficit Hyperactivity Disorder (ADHD) and its component symptom dimensions; clarifying the causes of comorbidity among ADHD, Oppositional Defiant Disorder (ODD), and Conduct Disorder (CD); clarifying the causes of comorbidity among anxiety disorders and depression and the role of personality therein; examining the role of specific environmental influences and candidate genes within behavior genetic models; and examining convergent and discriminant validity of laboratory measures and behavioral ratings of inattention, impulsivity, and related constructs within a behavior genetic framework.
Address: mailing address - Department of Psychology, 532 N. Kilgo Circle, Emory University, Atlanta, GA 30322, phone - (404) 727-7430, fax - (404) 727-0372, e-mail - waldman@fs1.psy.emory.edu
1Department of Psychology, Emory University, Atlanta, GA 30322.