IDENTIFICATION OF A COHORT OF MALE AND FEMALE TWINS AGED 65 YEARS OR MORE IN THE UNITED-STATES

In this paper, a method with which to identify a national cohort of el derly twins is proposed. Record linkage algorithms were developed and applied to the > 30 million records contained in the Medicare benefici ary file. The matching algorithm for male/male pairs used race (black or white), last name, date of birth, and state of issuance of the Soci al Security number. Female/female and male/female pairs were selected with matching on race, date of birth, and the first seven digits of th e Social Security number to compensate for the absence of maiden names . A stratified random sample of same-sex and opposite-sex white and bl ack pairs (six groups) were selected and surveyed for determination of the actual prevalence of twins. On the basis of these results, the au thors conclude that this method could identify an estimated 18,308 mal e/male, 7,544 female/female, and 204 male/female pairs of twins aged 6 5 years or more. This would be the largest sample of older twins ever assembled in the United States and represents a significant new resour ce for epidemiologic studies of the aging population.