Statistical methods in public health: the influence of Alexander D. Langmuir.

"The basic operation of the epidemiologist is to count cases and measure the population in which they arise" (1, p. 349). With this statement, Alexander D. Langmuir emphasized the critical role of statistical methods in public health practice. Public health is a population-based discipline that depends on science from other fields (2, p. 44), and a fundamental public health activity is the scientific measurement of health status. Toward this goal, statistical methods provide the scientific basis for identifying health problems, establishing objectives for health promotion and for disease and injury prevention, setting priorities for allocation of health care resources, and determining the impact of specific interventions. In this paper, we document Langmuir's role in the contribution of statistical methods to public health practice in the United States. We describe Langmuir's direct and indirect roles in the historical development of statistical science at the Centers for Disease Control and Prevention (CDC), state and local health departments, and academia, with specific attention to the influence that statistical methods have had on policy in public health. Finally, we discuss the future directions of statistical research in public health.