BACKGROUND:

The Vietnam Veteran Twin Registry, maintained by the NAS-NRC, was created with funding from the Veterans Administration. Department of Defense records were searched for subjects born between 1939-1957 and having the same last name and date of birth. Follow-up of induction records determined if the subjects were twins.

The registry supplemented the older World War II Veterans Twin Registry supported by the National Heart, Lung, and Blood Institute. The new registry provided an opportunity to create a resource with Black and Hispanic twins as well as whites. The new registry also included data on greater educational, socioeconomic, and lifestyle diversity than was available in the World War II Veterans Twin Registry.

DESIGN NARRATIVE:

During the first year a mailed questionnaire was designed which provided baseline data on family history, body size, morbidity, psychosocial characteristics, smoking, alcohol consumption, diet, physical activity, and drug use. The baseline data were used for analysis of cardiovascular, pulmonary, and blood diseases, and for follow-up. From the original survey, the Veterans Administration provided magnetic tape data on zygosity, smoking, alcohol consumption, heart, lung, and blood diseases, discharge rank, education, occupation, and family income. The questionnaire was completed by almost 8,900 individuals including over 3,000 twin pairs.