Mass X-Ray Service Mr. Meacher asked the Secretary of State for Social Services whether he will provide the cost-benefit figures, in relation to other expenditure within the overall health budget, on which he based his decision to run down the provision of the mass X-ray service. Mr. Alison The decision to run down this service was not taken primarily for reasons of economy, but because general population surveys now reveal relatively few cases of active tuberculosis for the number of persons examined. The service will continue to be used for surveys of population groups at special risk; and in some areas to meet the needs of general practitioners.