Validity — the quest for reality in quantitative and qualitative research

It has been argued that fundamentally different methodological approaches have made for ‘two sociologies’. This view has obscured the fact that the problem of validity has to be tackled independently of any specific methodological premises because of the textuality of sociological data. This does not necessarily imply, however, a single, unified strategy for validity testing. In this paper, some basic theoretical presuppositions underlying the approach to validity testing in quantitative research will be contrasted with the strategies offered by Max Weber's methodological writings on the ideal type. It is argued that the use of ideal typical constructs in qualitative research (exemplified by patient's illness careers) allows systematic validity testing despite the important differences in the conceptualization of social reality which is used in quantitative research, thus serving the purpose of any empirical sociological research, that is, to gain valid insight into societies' concrete reality.