The automated systems for prophylactic health examination represent screening diagnostic information systems whose functionality is based on appropriately organized and formed information and software support — a data set and data processing algorithms. The experience in the development and use of screening diagnostic systems has allowed us to build a formal model of an automated prophylactic health examination system. Using the formal model the problem of development of automated systems of such type can be reduced to that of synthesis of information structures with an invariant interpretation kernel and a set of decision rules applied to various sets of primary medical data and data processing results. This approach allows one to essentially simplify decision rule modification based on the results of the system operation practice and also to apply the obtained decision rules to different contingents of patients with minor changes in software.