Population density and the rate of mental illness.

An examination of age specific rates of psychiatric admissions within Brooklyn, New York, indicated that population density may function as an intervening variable in the production of mental illness. Measures of household and family contact were found to be significantly correlated to four rates of hospital utilization. These same measures carried unique components that were also significantly related to service use. Other measures of density such as people per acre and structures per acre were found to be unrelated to the rates of psychiatric utilization. The results of this study suggest that if density does produce mental illness its likely mechanism of action will be routed through household contact.