Dayaratne, D.A.R.K., Sumathipala, A., Fernando, D.J.S., Siribaddana, S.H., De Silva, N., & Abeysingha, N.
10th International Congress on Twin Studies, South Kensington, London | International Society for Twin Studies
Twin Research and Human Genetics, Volume 4, Issue 3, Page 177, Abstract 054P
Abstract
To expand the National Twin Registry of Sri Lanka to a population based register, we examined the feasibility of tracing older twins by inspecting birth records and recruiting them by postal invitation and in-person contact.
Methods. Birth records at a divisional secretariat reported from 2 maternity hospitals between the years of 1954–1970 were scrutinised randomly to identify twins. These 2 hospitals had the highest twin delivery rates for the whole country. We identified 310 twin pairs and a postal questionnaire was sent. Research assistants visited a cohort of non-respondents (71) in the postal survey.
Results. 620 twins were identified after perusing 20,700 birth records. Estimated twining rate, was 14.98 twin births for 1000 registered births for a year. In the postal survey, 37 (12%) responded and 62 letters were returned (20%), as twins were no longer in the postal address. Both were living in 20 pairs, one each in 15 pairs, and both dead in 2 pairs. In the field visits, 42 (59.2%) addresses were located. Information was available on 16-twin pairs Both were living in 8 pairs, one each in 4 pairs, and both dead in 4 pairs. At least one twin was traced in 10 pairs (14%). Both postal and field survey gave a low yield. This finding is different from tracing younger twins born between 1985–1997 by using the same methods. Migration, urbanization and development in the country may have affected tracing older twins’ from the birth record addresses, which are decades old.