[A few remarks on the subject of correct planning of epidemiologic studies]

The paper presents some problems on the planning of epidemiological studies. The definition of epidemiology is related to medicine, statistics, sociology, demography and other branches of science. Different types of epidemiological studies are enumerated (descriptive, analytical and experimental epidemiology, retrospective and prospective analysis). In the plan of epidemiological studies fifteen stages are distinguished and described. Special attention is given to the aim and object of research, sources of data, methods and techniques of evaluation, presentation and the analysis of results. The consequences of working without plan or with incomplete and wrong plan are presented. The authors suggest how to develop modern epidemiology in Poland.