How to combine pre-test and trial study? Case of European Social Survey 2004

Survey research used to be preceded by pilot studies. This article shows how one can combine two kinds of them, namely: pre-test and trial study. Pre-tests are carried out on small samples, and their results are analyzed in qualitative way. Trial studies are conducted on samples of several hundred cases and collected data are subjected to quantitative analyses. Original methodology established in pilot study for the European Social Survey combines quantitative and qualitative analyses and allows to overcome constraints met when the pre-test and trial study are carried out separately