Data management in metaanalytical procedures: Myths, realities and biases

The aim of the present paper is to highlight the importance of a correct data management and the preparation of a proper statistical value base in developing a meta-analysis. When dealing with meta-analytical procedures, research studies encounter a wide range of challenges, ranging from the classical value losses towards more modern coding or sampling biases. The theoretical and practical examples of this paper indicate that a meta-analytical approach is most useful and applicable when related to a clear problem specification, a correct coding scheme and the use of eligible study reports.