On the validity of language: Speaking, knowing and understanding in medical geography

This essay examines methodological problems concerning the conceptualization and operationalization of phenomena central to medical geography. Its main argument is that qualitative research can be strengthened if the differences between instrumental and apparent validity are better understood that the current research in medical geography suggests. Its premise is that our definitions of key terms and concepts must be reinforced throughout the design of research should our knowledge and understanding be enhanced. In doing so, the paper aims to move the methodological debate beyond the simple dichotomies of quantitative vs qualitative approaches and logical positivism vs phenomenology. Instead, the argument is couched in a postmodernist hermeneutic sense which questions the validity of one discourse of investigation over another. The paper begins by discussing methods used in conceptualizing and operationalizing variables in quantitative and qualitative research design. Examples derive from concepts central to a geography of health-care behavior and well-being. The latter half of the essay shows the uses and misuses of validity studies in selected health services research and the current debate on national health insurance.