[Epidemiologic study of regional inequalities]

The technological achievements of the recent years and the need for more advanced control of the processes within the health sector have supported the geographical epidemiology to become a distinct branch of epidemiology. The combined application of the simple standardized rates, statistical tests and different corrected risk parameters is able to describe the health status for geographically defined, small populations. Several statistical processes have been elaborated to estimate the number of the false positive results and to evaluate the role of chance in predicting the observed geographical pattern. These data completed with the usual risk measures quantify the risk difference within a broader region and determine the actual risk levels for the investigated small areas. The routine data processing system operating as a part of the public health surveillance identifies the high risk areas (the clusters) and without leaving the framework of routine data handling investigates the association between basic exposure data and health risks producing additional data about the nature of the aggregation of health related events. All the spetially varying etiological factors (environmental effects, social status, traditions, regional features of the health sector etc.) are ready to elicit regional alterations in the health status. The aim of the geographical information system is to cover the consequences of the uneven distribution of these factors. Since these kind of etiological factors play significant role in the generation of the most important public health problems in Hungary, and it is known that the small area inequalities are profound for these health impairments, the more extensive application of geographical information systems is expected to improve the efficiency of the control for public health problems and the performance of preventive medicine.