The impact of recruitment on research

'Nonetheless, the use of convenience samples place limitations on the kinds of inferences drawn from research. In the end, we strongly endorse the idea that psychological science will be improved as researchers pay increased attention to the attributes of the participants in their studies.'

From a study by Witt, Donnellan and Orlando of selection effects in psychology studies, reported in the BPS Research Digest. And just as true for design research.

[via Ben Goldacre]