Contents

21 November 1986
Vol 234, Issue 4779

About The Cover

Epidemiology, a field concerned with understanding health and disease in humans, focuses on health problems in populations rather than in individual patients. Advances in clinical medicine, laboratory science, statistics, and data handling in our basic understanding of the pathogenesis of disease have enabled epidemiologists to better examine causes of disease and to propose more effective strategies for prevention and control. See page 951. [Cover illustration by Alan Kahan, Washington, D.C.; photography by Donna K. Cantor, Washington, D.C.]