Beyond a shadow of a doubt? Experts, lay knowledge, and the role of radiography in the diagnosis of silicosis in Britain, c. 1919-1945.

The history of silicosis provides an important chapter in the history of occupational and environmental health. Recent historical scholarship has drawn attention to the importance of patient attitudes, popular protests, and compensation claims in the formation of a "lay epidemiology" of such a disease, frequently challenging the scientific orthodoxies devised by large corporations and medical specialists. Surprisingly little research has been undertaken on the United Kingdom, which provided much of the early expertise and medical research in respiratory diseases among industrial workers. This article examines the introduction of a particular technique, x-radiography, and its use by radiologists and others in debates on the causes and consequences of silica inhalation by the laboring population in Britain during the early decades of the twentieth century. In contrast to some recent interpretations, and also to the narrative of progress that practitioner historians have developed since the 1940s, this article suggests that the use of this technology was contested for much of this period and the interpretation of X-rays remained disputed and uncertain into the 1950s. The article also questions recent accounts of lay epidemiology as an adequate model for understanding the progress of such innovations in medical history.