that the load foran individual participant in an investigation isoften unreasonably large: to be ready for aninterview and in addition to provide a coun-selling conversation is, if measured against thenormal requirement of taking part in a study, acomparatively heavy burden.

how comparability of the samples

ecause of projectplanning and resources, the empirical steps haveto be conducted sequentially – first the observa-tional data are collected and analysed and thenthe interviews are conducted and analysed. Inthis case possible influences of the differenttimes on content should not be forgotten