@article {Sumathipala:1 December 2000:1369-0523:205,
	author = "Sumathipala, A.",
	author = "De Silva, N.",
	author = "Siribaddana, S.H.",
	author = "Abeysingha, M.R.N.",
	author = "Fernando, D.J.S.",
	title = "Establishing a twin register in Sri Lanka",
	journal = "Twin Research",
	volume = "3",
	year = "1 December 2000",
	abstract = "We report the process of adaptation into Sinhala of a questionnaire given tomothers of twins to determine zygosity. Adaptation and validation was carriedout in three stages. Firstly, we used a nominal group to translate the Englishversion and to assess the extent of agreement (consensus measurement) on theappropriateness of the translation and resolve disagreement (consensusdevelopment). Secondly we used a qualitative interview with 25 mothers of twins.The three main stems of the translated questionnaire were used as a semi-structured interview, and the responses noted verbatim. These were categorisedand analysed, and the translated full questionnaire was then presented as closedquestions with fixed choice responses. The categorised responses generatedduring the qualitative interview were compared with the responses to the fixedchoices in the full questionnaire. The third stage was the appraisal of thequestionnaire by 17 bilingual parents of twins. The source and translated versionof the questionnaire were given to them at least 3 days apart. The responses wererated and the total scores were computed to determine the zygosity. This step wascarried out to measure the validity and reliability of the Sinhala version. Aperfect correlation between the original and adapted version was obtained, with akappa of 1. The results suggest that the Sinhala version of the questionnaire isconceptually equivalent to the original questionnaire. Comparison of the zygositydetermination by using this adapted questionnaire with results from analysis ofgenetic markers on Sri Lankan twins is needed for final validation of thetranslated questionnaire.",
	pages = "205-212(8)",
	url = "http://www.ingentaconnect.com/content/aap/twr/2000/00000003/00000004/art00004"
	doi = "doi:10.1375/136905200320565166"
}