§ Mr. Llew SmithTo ask the Secretary of State for Wales what reliability tests were applied to the data collected in the Welsh health survey questionnaires conducted in 1995. [6067]
§ Mr. Gwilym JonesThe Welsh health survey questionnaire was for the most part made up of well-tested questions of proven reliability. A pilot survey was carried out in December 1994 using a random sample of 1,000 adults living in Wales to test all the questions and survey methods used.
A random sample of the completed questionnaires was validated by hand, comparing the respondents' answers with the corresponding keyed-in data.
Details of other steps taken are given in appendices 1, 2 and 3 of the survey report—Welsh health survey 1995. A copy is in the Library of the House.