Commentary: The prevention paradox in lay epidemiology—Rose revisited

‘It has long been a commonplace observation in the discipline of social anthropology that cultural systems of explanation or accountability [for the occurrence of a misfortune] need to address two distinct issues. In the first place the general kind of misfortune: how and why does it happen? In the second place, the site and time of particular misfortune require explanation: how and why did it happen to this person at this time? … In our own society, where the development of science has shaped so many other cultural institutions, it is sometimes overlooked that this pair of explanations is still required. This is so because it is a central pillar of the Western scientific tradition that the two explanatory systems are unified.’ 1(p.4) Rose’s seminal paper 2 contrasting the consequences of a focus on sick individuals with that on sick populations, stresses the importance of distinguishing between two kinds of aetiological questions, and in so doing demonstrates immediate parallels with the model of anthropological enquiry presented above. In Rose’s terms, within the province of predicting and explaining the occurrence of illness, one aetiological question seeks to establish the causes of cases (i.e. the occurrence of a specific disease in a specific individual at a specific time); and the second is concerned with the causes of incidence. Rose opens his paper by drawing attention to the question which he has ‘often encouraged’ medical students to consider when teaching them epidemiology: ‘Why did this patient get this disease at this time?’ This he describes as an ‘excellent starting-point’ given their ‘natural concern for the problems of the individual’. We would argue that this is also the starting point for the lay epidemiologist and that the concerns of the clinician and the (nascent) epidemiologist have much in common with the lay epidemiologist. Our use of ‘lay epidemiology’ follows Davison et al. who describe this as ‘a scheme in which individuals interpret health risks through the routine observation and discussion of cases of illness and death in personal networks and in the public arena’ 3 (expanded below). This is in contrast to the notion of ‘popular epidemiology’, as framed by Brown, 4 which represents public participation in ‘traditional’ (or formal) epidemiology, often through lay advocacy to highlight hitherto ignored environmental hazards or risks such as toxic waste (see also 5 ). Rose then asserts that an ‘integral part of good doctoring’ is to ask ‘Why did this happen, and could it have been prevented?’ (p.32) The questions drawn out by Davison et al. in relation to anthropology and Rose in relation to the practice of medicine and the teaching of epidemiology illustrate the centrality of the prevention paradox to lay epidemiology.