This article examines how problems of validity in empirical social research differ from those in natural science. Specifically, we focus on how some ontological peculiarities of the object of study in social science bear on validity requirements. We consider these issues in experimental validity as well as in test validity because, while both fields hold large intellectual traditions, research tests or questionnaires are less closely connected to natural science methodology than experiments.

There have been calls for some time for a new approach to public health in the United Kingdom and beyond. This is consequent on the recognition and acceptance that health problems often have a complex and multi-faceted aetiology. At the same time, policies which utilise insights from research in behavioural economics and psychology have gained prominence on the political agenda. The relationship between the social determinants of health and behavioural science in health policy has not hitherto been explored. Given the (...) on-going presence of strategies based on findings from behavioural science in policy-making on the political agenda, an examination of this is warranted. This paper begins by looking at the place of the SDoH within public health, before outlining, in brief, the recent drive towards utilising behavioural science to formulate law and public policy. We then examine the relationship between this and the SDoH. We argue that behavioural public health policy is, to a certain extent, blind to the social and other determinants of health. In section three, we examine ways in which such policies may perpetuate and/or exacerbate health inequities and social injustices. We argue that problems in this respect may be compounded by assumptions and practices which are built into some behavioural science methodologies. We also argue that incremental individual gains may not be enough. As such, population-level measures are sometimes necessary. In section four we defend this contention, arguing that an equitable and justifiable public health requires such measures. (shrink)