Screening: mapping medicine's temporal spaces.

This paper examines the history of population screening through an analysis of contemporary medical journals. The term was first used in the modern sense in the inter-war years to describe the school health examination which sought to identify the early signs of disease and abnormality, a strategy which was extended to new recruits during the Second World War. After the war, screening began to target those illnesses in the civilian population which had a clear temporal trajectory, especially 'chronic' illnesses. Since the 1980s, enthusiasm for population screening has declined within the medical community: opportunistic screening has seemed more appropriate for diseases with multifactorial aetiology, and those programmes which have survived have been increasingly challenged through an expanding analysis of their potential harms. In identifying the early precursors of clinical disease in apparently normal populations, however, screening heralded the emergence of a new form of clinical practice concerned with the surveillance of 'healthy' patients within the context of new temporal spaces of illness.