We will estimate the incremental health service cost per additional completed Health Check for trial groups B and C versus trial arm A , as well as evaluating the impact of the QBE questionnaire , and questionnaire plus voucher , on the socioeconomic inequality in uptake of Health Checks.The trial includes a nested comparison of two methods for implementing allocation , one implemented manually at general practices and the other implemented automatically through the information systems used to generate invitations for the Health Check .