The earliest sickness survey of the US Public Health Service, which started in 1915, was the Service’s first socioeconomic study of an industrial community. It was also the first to define illness as a person’s inability to work. The survey incorporated the Metropolitan Life Insurance Company’s definition of illness, which, instead of sickness rates, focused on duration of illness as a proxy of time lost from work. This kind of survey took place in the broader context of the reform movements of the Progressive Era and the social surveys conducted in the United States, which led to the creation of the Federal Commission on Industrial Relations, where the Service’s sickness survey originated. The Service’s focus on the socioeconomic classification of families and definition of illness as the inability to work enabled it to show the strong link between poverty and illness among industrial workers. The leader of the survey, Edgar Sydenstricker, and the Metropolitan Life Insurance Company came up with new ways to measure the health of the population, which also influenced the Service’s studies of the effects of the Great Depression on public health and the National Health Survey of 1935-1936
