§ Mr. Dykes
asked the Secretary of State for Social Services when the sample survey of incomes which was intended as 299W a follow-up of the 1971 Census of Population will take place; and if he will make a statement.
§ Sir K. Joseph
The survey will begin tomorrow, 22nd March. It will be carried out by the Office of Population Censuses and Surveys and the General Register Office, Scotland, but, unlike the census, participation in it will be entirey voluntary.
The survey will seek information on all main sources of income and will provide statistics on household and personal incomes which can be related to other data already collected in the census. The statistics are much needed as background information in the development of policies for many of the social and economic problems that face us.
The survey will be entirely confidential. No information relating to any person or household will be passed to anyone outside the census organisation and the information collected will be used only to produce anonymous statistics from which no one can be identified.
The questionnaires have been so designed that no names and addresses will appear on the completed form, merely an identification number known only to a very limited number of the staff of the census offices. The procedures have also been designed so that no person need show his completed form to any other person in the household.
Questionnaires will be sent to all persons aged 15 and over in one per cent. of households—about 180,000—and to 1 per cent. of persons aged15 and over usually resident in institutions such as hotels and boarding houses. Members of the sample will be selected at random.
The survey will be carried out in two stages. The first batch of questionnaires will be posted tomorrow and the remainder in June. Respondents are being asked to return their completed forms by post to the Office of Population Censuses and Surveys or General Register Office, Scotland. Each stage will be followed by a small number of voluntary interviews designed to identify difficulties met with in filling in the forms and to assess the quality of the replies.
My right hon. Friend, the Secretary of State for Scotland and I will be sending 300W letters to everyone chosen in the sample, explaining the need for the information and also the voluntary and confidential nature of the enquiry.
Although this is a voluntary inquiry, the importance of the information to be collected is such that my right hon. Friend and I hope that everyone selected in the sample will take part.