Mortality in relation to the physical activity of work: a preliminary note on experience in middle age.

In the course of studies of the epidemiology of coronary heart disease the suggestion arose that deaths from this condition in middle age may be less common among men engaged in physically active work than among those in " sedentary " jobs (Morris, Heady, Raffle, Roberts, and Parks, 1953). In testing this hypothesis an analysis was made of data in the Registrar General's Decennial Supplement for 1930-32 on occupational mortality (1938). The 70 occupational groups in social classes III, IV, and V, the skilled, semi-skilled, and unskilled workers for whom information is provided (about two and a half million men,