Neiderhiser Jenae M, Reiss David, Hetherington E Mavis
Center for Family Research, Department of Psychiatry & Behavioral Sciences, George Washington University, Washington, DC 20037, USA.
Twin Res Hum Genet. 2007 Feb;10(1):74-83. doi: 10.1375/twin.10.1.74.
The Nonshared Environment in Adolescent Development (NEAD) project is a longitudinal study of twins/siblings and parents that has been assessed 3 times: middle adolescence, late adolescence and young adulthood (N=720 families at Time 1). Siblings varied in degree of genetic relatedness including identical twins, fraternal twins, full siblings, half siblings and genetically unrelated (or step) siblings. There were also two family types: nondivorced and step. A multimeasure, multirater approach was taken in NEAD, with data collected from all participants (2 twins or siblings, mother and father) as well as from coded videotaped observations of family interactions. Detailed assessments of family relationships, adolescent adjustment and competence were collected at all 3 times. The original aim of NEAD was to identify systematic sources of nonshared environmental influences that contribute to differences among family members. Although systematic sources of nonshared environmental influences were not found in NEAD, three major sets of findings emerged: (1) genetic influences on family relationships and on associations between family relationships and adolescent adjustment; (2) genetic and environmental influences on adolescent adjustment, comorbidity and stability and change in adolescent adjustment from middle to late adolescence; and (3) genetic influences on relationships outside the family.
青少年发展中的非共享环境（NEAD）项目是一项针对双胞胎/兄弟姐妹及其父母的纵向研究，该研究进行了三次评估：青春期中期、青春期后期和青年期（第一次评估时N = 720个家庭）。兄弟姐妹在遗传相关性程度上存在差异，包括同卵双胞胎、异卵双胞胎、亲兄弟姐妹、半同胞兄弟姐妹以及无血缘关系（或继）兄弟姐妹。此外，还有两种家庭类型：未离异家庭和再婚家庭。NEAD采用了多测量、多评估者的方法，收集了所有参与者（2对双胞胎或兄弟姐妹、母亲和父亲）的数据，以及对家庭互动的编码录像观察数据。在所有三次评估中都收集了关于家庭关系、青少年适应能力和能力的详细评估。NEAD的最初目标是确定导致家庭成员之间差异的非共享环境影响的系统来源。尽管在NEAD中未发现非共享环境影响的系统来源，但出现了三大组研究结果：（1）遗传对家庭关系以及家庭关系与青少年适应之间关联的影响；（2）遗传和环境对青少年适应、共病以及青少年从青春期中期到后期适应的稳定性和变化的影响；（3）遗传对家庭外关系的影响。
