Patterns of mortality in middle and early old age in the county boroughs of England and Wales.

It is common knowledge that death rates vary from area to area, year to year, and between different groups of the population. These differences have been extensively studied but, very often, only in relation to a particular cause of death or a particular feature of the environment-the association of bronchitis with air pollution, for example, or population density with respiratory death rates. This paper, reporting a fairly comprehensive search for associations between the environment and death rates from four major 'causes' at ages 45-74 in the large towns of England and Wales, has, as its reason, the systematic presentation of some accepted facts and the posing of new, as well as continuing, questions.