The effect on the patient flow in local health care services after closing a suburban primary care emergency department: a controlled longitudinal follow-up study.

Manipulating distances to ED services can be used to direct patient flows to different parts of the health care system. The correlation between distance to ED and the tendency to use ED by inhabitants is negative. If secondary care ED was available there were no life-threatening side-effects at the level of general public health when a minor ED was closed in a primary care ED system.